LSAC LSAC Certifications LSAT-TEST Questions & Answers

• Question 321:

  A study of young and middle-aged men in the United States has found that the men whose diet was high in saturated fat also had a high amount of blood cholesterol. In another experiment, when the blood cholesterol level of laboratory rabbits was raised by feeding them exclusively on cholesterol, fat deposits formed in their blood vessels. Similar fat deposits are found in human patients of heart disease. Therefore, to reduce the occurrence of heart disease, people should reduce their dietary consumption of saturated fat.

  Each of the following, if true, weakens the above argument EXCEPT:

  A. The bodily reactions of animal models to internal or external stimulants are often poor predictors of the reactions of the human body to the same stimulants.

  B. The per capita consumption of saturated fat in the United States has decreased by 27 percent since 1970 while the occurrence of heart disease in the country has increased by 400 percent in the same period.

  C. An analysis of studies done on more than 600,000 men and women has established that blood cholesterol is inversely associated with the risk of death from infectious respiratory and digestive diseases.

  D. A study that covered more than 10,000 individuals has found no relationship between the amount of blood cholesterol and the occurrence of heart disease.

  E. In a study where the dietary saturated fat consumption of young and middle-aged American women was three to seven times higher than normal, the blood cholesterol level remained unchanged.

  Correct Answer: C

  Argument construction Premise 1: A study of young and middle-aged men in the United States has found that the men whose diet was high in saturated fat (SF) also had a high amount of blood cholesterol (BC).

  So, this premise can be simplified as: High SF is correlated with high BC in young and middle-aged American males.

  Premise 2: In another experiment, when the blood cholesterol level (BC) of laboratory rabbits was raised by feeding them on cholesterol, fat deposits (FD) were found in their blood vessels.

  This premise can be simplified as: In lab rabbits, when BC became high, FD formed.

  Premise 3: Similar fat deposits (FD) are found in human patients of heart disease (HD).

  So, per this premise, FD is correlated with HD in humans.

  By combining these three premises, the following conclusion is drawn:

  Conclusion: To reduce the occurrence of heart disease, people should reduce their dietary consumption of saturated fat.

  In simpler form: To reduce HD, people should reduce SF.

  The structure of this argument can be visually depicted as under:

  

  There are a few things to note about the way this argument is drawn:

  The argument's conclusion draws broad generalizations whereas the premises are not similarly general in

  their scope:

  1.

  Premise 1 mentions a finding about one demographic - young and middle -aged American men ?while the conclusion drawn is a generalization that seems to apply to all";people"; irrespective of age, gender or

  nationality.

  2.

  Premise 2 mentions a finding about laboratory rabbits while the conclusion drawn is about humans. The argument confounds correlation with causation.

  This is proved by the conclusion that reducing SF will cause reduced occurrence of heart disease. However, the premises do not offer grounds for such causality:

  1.

  Premise 1 only states that in one particular group, high SF is correlated with high BC. We cannot infer from this whether it is high SF that caused high BC, or whether high BC caused high SF (for example, by inducing cravings for food that is high SF), or whether some other third factor was the cause of both high SF and high BC (for example, if the individuals of this particular group have a genetic predisposition towards higher BC than other ethnic and/or age groups and also have a diet that is high in SC).

  2.

  In Premise 2, since FD follows an increase in BC, the said increase in BC does seem to cause the FD; however, this causal link is still an assumption and is not explicitly stated by the argument. Alternate explanations might be possible. For example, since these rabbits were fed exclusively on cholesterol, perhaps they developed deficiency of some vital nutrient X (which they usually got from their normal diet) and it was the lack of this nutrient X that caused the formation of FD. With such an explanation, one can see that if the rabbits had continued to consume as much cholesterol as they did in this study but along with the required amounts of X, they would not have formed FD.

  3.

  In Premise 3, FD is found in human patients of HD. This is not enough to conclusively establish that FD causes HD in humans. For example, when the virus of common cold enters the human body, the body activates its immune system and produces antibodies to neutralize that virus. There is a brief period when, if a blood sample is taken from the body, both the virus and the antibodies will be found in it. From this coexistence, drawing a conclusion that the antibodies produced/caused the virus would be wrong. Correlation does not always imply causality, and even when it does, the direction of that causality is not always clear (if A and B coexist, then does A cause B or does B cause A?).

  Not only does the argument make an unreasonable assumption that high SF causes high HD, but it also assumes that the converse of this statement would be true ?that is, low SF would cause low HD.

  1.

  The evidence presented in premises 1 and 2 is about high SF and high blood cholesterol. Using this evidence to draw the conclusion that low SF would have the opposite effect to that of high SF is fallacious.

  2.

  For example, the following statement is true: "high stress causes high blood pressure." However, the converse of this - "low stress causes low blood pressure" ?is not true.

  This is a 'Weaken EXCEPT' question. Therefore, four of the answer choices will weaken the argument. We will be looking for the single statement that does not weaken it.

  Let us analyze the options one by one.

  Answer choices explanation

  [The bodily reactions of animal models to internal or external stimulants...] This option is incorrect. This statement does weaken the argument by suggesting that the use of premise 2 (which describes the bodily reaction of an animal model to high BC) to draw a conclusion about the bodily reaction of the humans to high BC may not be correct. Without this premise, the conclusion cannot hold.

  [The per capita consumption of saturated fat in the United States has decreased...] This option is incorrect. This statement does weaken the argument by providing empirical evidence that in the same period in which SF decreased, HD increased by a lot more. This suggests that some factor, other than SF, causes HD and therefore disproves the causal assumptions that went into the drawing of the conclusion.

  [An analysis of studies done on more than 600,000 men and women has...] This option is correct. This statement does not weaken the argument. From this statement, we learn some benefits of high blood cholesterol and risks of low blood cholesterol. However, the argument's main concern was not whether the overall impact of high blood cholesterol on human health is beneficial or not. The argument suggests only one specific effect of high blood cholesterol ?that it causes heart disease. Likewise, the conclusion is only concerned about reducing HD. If reducing HD by reducing SF has some other side-effects (like increased risk of infections, as this option statement seems to suggest), then so be it. These are "other" side-effects and are outside the scope of the argument. The author is only claiming that reducing SF will reduce HD. He is not claiming that reducing SF will reduce the occurrence of all kinds of diseases.

  [A study that covered more than 10,000 individuals has found...] This option is incorrect. This statement weakens the argument. It states that in humans, high blood cholesterol does not lead to HD. This directly disproves the subsidiary conclusion that can be drawn by combining premises 2 and 3 while also assuming that correlation implies causation, this subsidiary conclusion being that high blood cholesterol leads to HD.

  [In a study where the dietary saturated fat consumption of young...] This option is incorrect. It weakens the argument. It shows that the extrapolation of premise 1 to all humans (as has been done in the argument) was incorrect. When females of a similar age-group and nationality as the men in the study that is cited in premise 1 ate a high SF diet, their blood cholesterol did not increase. This suggests that there is not a simple causal link between high SF and high BC. The chain of causations on which the conclusion rests therefore stands broken.

• Question 322:

  This year, the cotton crop in Alabama has been attacked by a new, hardy variety of bollworm that is resistant to all known pesticides. Due to this, the cotton production of the state has declined by 40 percent this year. Since this bollworm variety reproduces rapidly, it is likely to spread through all cotton-producing states of the United States by the next year and, therefore, we can expect a decline of at least 40 percent in the amount of cotton produced in the country next year. Which one of the following, if true, most weakens the argument?

  A. Many other crops in Alabama too have been attacked by this bollworm variety this year.

  B. The natural predators of this bollworm variety are not able to survive in Alabama while cotton-farms in other cotton-producing states have large populations of these predators.

  C. Ninety-five percent of all cotton produced in the United States is of the Upland variety, which is also the only variety of cotton that is grown in Alabama.

  D. The domestic prices of cotton are not likely to increase next year as the United States will be able to meet its domestic demand for cotton through imports.

  E. Agricultural scientists in the United States are making a massive effort to soon develop a variety of genetically-modified cotton that is resistant to this bollworm variety.

  Correct Answer: B

  Argument construction

  This year:

  "the cotton crop in Alabama has been attacked by a new, hardy variety of bollworm that is resistant to all

  known pesticides." This is context-setting information.

  "Due to this, the cotton production of the state has declined by 40 percent this year." This is Premise 1.

  Premise 2: "this bollworm variety reproduces rapidly."

  Premise 2 leads to a Subsidiary Conclusion: "[this bollworm variety] is likely to spread through all cotton-

  producing states of the United States by the next year."

  Premise 1 and the Subsidiary Conclusion are then combined to reach the Main Conclusion: "we can

  expect a decline of at least 40 percent in the amount of cotton produced in the country next year."

  There are a few gaps in the way this argument has been made:

  It has been assumed that what has happened in Alabama will happen in all cotton-producing states of the

  country. Premise 1 mentioned a 40 percent decline in cotton production in only Alabama. However, using

  this premise, a conclusion was drawn that there will be a 40 percent decline across all cotton-producing

  states of the country next year. Clearly, this generalization is unfounded and if attacked or proved wrong

  will significantly weaken the conclusion drawn in the argument.

  Another type of generalization that has been made in the argument is time-based. Premise 1 presents

  facts that happened this year. And using this premise, a conclusion is drawn about what will happen next

  year. Such extrapolation of this year's information to make a prediction for the next year is a logical leap

  and the argument will be weakened if a reason is provided for why this year ought not to be used as the

  basis of future predictions. For example, it could be that the weather in Alabama this year was unusually

  hot but it is expected to be normal again the next year. In this case, the bollworm variety, which thrives in

  unusually hot weather, may lie dormant or even perish next year because the weather next year may be unfavorable to it. Premise 2 offers only a very weak support to the subsidiary conclusion. Premise 2 mentions that this bollworm variety reproduces rapidly. For example, say, its population takes only 24 hours to double. This only suggests that its population in Alabama where this bollworm variety is found now will increase significantly by next year. But will it necessarily spread to other cotton-producing states? Does this bollworm variety have the physical capacity to travel long distances or some other means to travel or reach new places? If evidence is presented to suggest that the answer to these questions is No, then the Subsidiary Conclusion is proved wrong, and consequently the Main Conclusion gets significantly weakened.

  Let us analyze the options one by one.

  Answer choices explanation

  [Many other crops in Alabama too have been attacked by...] This option is incorrect. The conclusion drawn concerns only the cotton crop (across all cotton-producing states of the country, next year). The impact of this bollworm on other crops of Alabama does not impact the argument.

  [The natural predators of this bollworm variety are not able to survive in Alabama…] This option is correct. This statement suggests one reason why it would be wrong to use what happened in Alabama to make a prediction for what will happen in other cotton-producing states. A point of difference between Alabama and these other states is that Alabama does not have the natural predators of this bollworm variety, whereas the other states have these predators in large numbers. This suggests that in the other states, the population of this bollworm variety will be controlled (by natural predators present in cotton forms) and therefore, it will not be able to wreak as much havoc as it did in Alabama this year. Therefore, when this option statement is used in conjunction with Premise 1, the main conclusion appears much weaker.

  [Ninety-five percent of all cotton produced in the United States is of the Upland variety…] This option is incorrect. Had the variety of cotton grown in Alabama been different from that grown in the other cotton-producing states of the United States, the conclusion would have been weakened. For example, one could have supposed that perhaps this bollworm variety had a deleterious impact on only the Alabama variety of cotton, and that its impact on the other varieties of cotton would be mellower or negligible. However, this option statement says that Alabama also grows the same variety of cotton that makes for 95 percent of all cotton grown in the United States. This option statement, therefore, establishes a point of similarity between Alabama and the other cotton-producing states and, thus, supports the use of Alabama-based Premise 1 to make a general conclusion for all cotton-producing states.

  [The domestic prices of cotton are not likely to increase…] This option is incorrect. The argument makes no prediction or claim regarding the domestic prices of cotton next year. Therefore, this option statement is out of the argument's scope.

  [Agricultural scientists in the United States are making a massive effort...] This option is incorrect. On the face of it, this option seems to suggest that the efforts of the agricultural scientists might prevent the predicted decline of cotton production next year by creating cotton plants that are immune to this bollworm variety. However, on closer inspection of the statement, we start to notice flaws in it. For example, the word "soon" is qualitative. What time frame does it convey? One month, or six months, or one year, or five years? This is not clear. On the other hand, the conclusion concerns itself very clearly with the next one year. Further, even if such a variety of cotton gets developed before next year, will it immediately get adopted on a large scale, across all cotton-producing states of the United States? This seems unlikely. Therefore, it does not seem plausible that these efforts of agricultural scientists will undermine the conclusion drawn by the argument.

• Question 323:

  A test that examines people on their memory capacity for spatial layouts has placed Jason in the top 1 percentile of all test-takers. We can conclude from this that his memory capacity for things that do not involve spatial layouts will be below average. The conclusion follows logically if which one of the following is assumed?

  A. Jason tried hard to remember spatial layouts.

  B. Jason has a greater proclivity to remember spatial layouts than most people.

  C. It is possible for Jason to improve, through practice and effort, his memory capacity for things that do not involve spatial layouts.

  D. The total memory capacity of the human brain is fixed and equal for all people.

  E. Some people have a greater memory capacity than others.

  Correct Answer: D

  Argument construction A test that examines people on their memory capacity for spatial layouts has placed Jason in the top 1 percentile of all test-takers. We can conclude from this that his memory capacity for things that do not involve spatial layouts will be below average.

  The structure of the argument is:

  Premise: Jason is in the top 1 percentile of all people in his memory capacity for spatial layouts. This means, his 'memory capacity for spatial layouts' (called Ms henceforth for easier reference) is better than 99% of all test-takers. In other words, it is outstanding!

  Conclusion: We can conclude from this that his memory capacity for things that do not involve spatial layouts (called MO ?'o' for other things - henceforth for easier reference) will be below average. Looking at this argument, we see a gap between the premise and conclusion ?being outstanding in MS does not necessarily guarantee that one's MO will be below average. This is the loophole that the correct answer choice will have to plug. The correct answer choice will be one which, when added to the argument's premise, would produce a conclusive argument, that is, an argument with no gaps in its support for the conclusion.

  Let us analyze the options one by one.

  Answer choices explanation [Jason tried hard to remember spatial layouts.] This option is incorrect. When we take this option statement as a premise and combine it with the premise of the argument, does the conclusion logically follow? No. This option statement only provides a plausible reason for why Jason's MS is outstanding. It does not offer any support for the conclusion, which is about his MO.

  [Jason has a greater proclivity to remember spatial layouts than most people.] This option is incorrect. The reasons are similar to the ones discussed in the Option above.

  [It is possible for Jason to improve, through practice and effort, his memory capacity for things that do not involve spatial layouts.] This option is incorrect. The premise in the argument is that Jason's MS is outstanding. The premise offered by this option statement is that it is possible for Jason (through practice and effort) to improve his MO. When these two premises are combined, the conclusion that Jason's MO is below-average does not logically follow. In fact, one wonders how, when it is possible to improve one's MO, can such a definite declaration as the argument's conclusion be made.

  [The total memory capacity of the human brain is fixed and equal for all people.] This option is correct. According to this option statement, the total memory capacity, M, is equal for all people. Also, M is a fixed number. It cannot be increased or decreased. Now, If Jason has higher MS than most people, then it does follow that his MO is lower than most people. Therefore, when this option statement is combined with the argument's premise, there is no gap left in the argument and the conclusion follows logically.

  [Some people have a greater memory capacity than others.] This option is incorrect. If some people have a greater (total) memory capacity than others, then it could be possible that Jason has both an outstanding MS and an outstanding MO, therefore, ending up with an outstanding total memory capacity M as compared to most people. Therefore, when this option statement is combined with the premise, the conclusion does not logically follow.

• Question 324:

  In the 1920s, surveys of factory workers who painted watch dials with luminous paint found an alarming incidence of anemia, loss of teeth, bone fractures and death from cancer. This paint contained radium, a radioactive element. As a result, the industrial use of radioactive luminous paint was completely stopped by 1960. However, radium stays active for hundreds of years. Therefore, those watch-collectors who own watches that have luminous dials and were made before 1960 should either bury these watches in the ground or store them in thick lead boxes to protect themselves and the people around them from anemia, loss of teeth, bone fractures and death from cancer.

  Which one of the following, if true, LEAST strengthens the argument above?

  A. The surveys also found that the incidence of anemia, loss of teeth, bone fractures and death from cancer among factory workers who painted watch dials with non-luminous paint was not greater than that among the general population.

  B. The surveys also found that factory workers who painted watch dials with luminous paint, the extent of their health problems was directly proportional to the cumulative number of hours for which they had worked with luminous paint till then.

  C. Barriers of lead or earth provide adequate protection to human beings from harmful radioactive substances.

  D. People who wear watches that have luminous dials and were made before 1960 for more than a decade have an alarming incidence of anemia.

  E. Most chemists and laboratory workers who worked with radium for more than a year in the first decade after its discovery in 1898 did not have, for the rest of their lives, a greater incidence of anemia, loss of teeth, bone fractures and death from cancer than the general population.

  Correct Answer: E

  Argument construction

  Premise 1:

  In the 1920s, surveys of factory workers who painted watch dials with luminous paint (WDLP workers)

  found an alarming incidence of anemia, loss of teeth, bone fractures and death from cancer (HP = Health

  Problems).

  This premise tells us that 'WDLP workers' had 'HP.'

  Premise 2:

  This paint contained radium, a radioactive element.

  WDLP would presumably have had many ingredients, one of which was radium ?a radioactive element.

  Subsidiary Conclusion drawn from Premises 1 and 2:

  As a result, the industrial use of radioactive luminous paint was completely stopped by 1960.

  The fact that this is a conclusion is suggested by the phrase 'as a result.' This conclusion also implies that

  those who had the power to decide what kind of paint was to be used on watch dials (the watch dial

  manufacturers, the government authorities etc.) assumed that 'WDLP workers' had 'HP' due to 'the radium

  in WDLP.'

  Also note that Premise 1 was only concerned with WDLP workers. However, the subsidiary conclusion

  extends to all industrial use of LP. So, the decision-makers mentioned in the above paragraph also

  assumed that if radium caused HP in WDLP workers, then it would also cause HP in other industrial

  workers.

  Premise 3:

  However, radium stays active for hundreds of years.

  So, the radium in the watches that were made before 1960 would still be active today, and, assuming the

  causal link between 'the radium in WDLP' and the 'HP of WDLP workers,' can cause HP even today.

  Main Conclusion:

  Therefore, those watch-collectors who own watches that have luminous dials and were made before 1960

  should either bury these watches in the ground or store them in thick lead boxes to protect themselves and

  the people around them from anemia, loss of teeth, bone fractures and death from cancer.

  The Main Conclusion makes use of some assumptions (unstated premises):

  Burying a radioactive material in ground or storing it in thick lead boxes is enough to protect humans from

  it.

  While Premise 1 presented an observation for WDLP workers, the main conclusion is drawn for watch-

  collectors. The author of the argument has assumed that what is true for WDLP workers would also be

  true for collectors of the

  watches made by these workers. This is a questionable extrapolation, as it might be expected that a

  worker who painted watch dials with WDLP day-in and day-out would have had a much higher exposure to

  radium than a watch-collector who only looks at his watch-collection occasionally and for only a few

  minutes per watch at a time.

  The Main Conclusion applies to a group of people (watch-collectors) in the present-time and the reason

  why watches made decades ago are still thought to pose a health hazard today is given in Premise 3,

  which states that radium stays

  active for hundreds of years. The main conclusion therefore depends on the assumption that it was the

  radium in the LP that caused the HP of WDLP workers. This assumption need not be correct. LP would

  have had many ingredients, one of which was Radium; no direct evidence is presented in the argument to

  indicate that it was Radium and not another ingredient of the LP that caused the HP of WDLP workers.

  Note that this is a Strengthen-Except question (If one option 'least' strengthens the argument, it follows that

  the other four options strengthen the argument). We are looking for the one answer choice that does not

  strengthen the argument.

  Let us analyze the options one by one.

  Answer choices explanation

  [The surveys also found that the incidence of anemia, loss of teeth, bone fractures and death from cancer

  ...] This option is incorrect. The group of workers mentioned in this option statement are the opposite of

  WDLP. These people did not use LP and, as per this option statement, they had no HP; the incidence of

  diseases mentioned in the argument among this group was the same as in the general population. So, 'the

  WD painters who used LP' had HP while 'the WD painters who did not use LP' did not have HP. This

  option statement strengthens the assumption that it was the LP that caused the HP in WDLP workers.

  [The surveys also found that factory workers who painted watch dials with luminous paint, the extent of

  their ...] This option is incorrect. The more LP that a WDLP worker was exposed to, the more HP he had.

  The less LP that a WDLP worker was exposed to, the less HP he had. This clearly strengthens the

  assumption that it was the LP that caused the HP in WDLP workers.

  [Barriers of lead or earth provide adequate protection to human beings from harmful radioactive

  substances.] This option is incorrect. This statement strengthens the main conclusion by validating an

  assumption on which it depends.

  [People who wear watches that have luminous dials and were made before 1960 for more than a decade

  have an alarming incidence of anemia.] This option is incorrect. This statement strengthens the main

  conclusion by providing evidence that under certain circumstances (when the antique watches are worn for

  more than a decade), watch-collectors too can suffer from at least some of the HP (anemia) that the WDLP workers of Premise 1 suffered from. Thus, this option statement validates an assumption on which the main conclusion depends.

  [Most chemists and laboratory workers who worked with radium for more than a year in the first decade...] This option is correct. This statement weakens the main conclusion because it provides evidence that there is a group of people who handled radium but who did not have HP. This suggests that an assumption on which the Main Conclusion depends - that the HP of the WPLD were caused by the radium in the LP ?is probably incorrect.

• Question 325:

  Astragalus linifolius, a rare plant species that is found only in the Colorado region of the United States, reproduces when a pollinating agent like a fly or a bee carries the pollen grain from the male part of one plant to the female part of another plant of the same species. To maintain the population of this species, the use of pesticides that control grasshoppers should be banned in this region. These pesticides also often result in significant mortality among the Bombylius flies that are the most important pollinating agents of Astragalus linifolius. Which one of the following, if true, most strengthens the argument?

  A. Astragalus linifolius has a short life-span.

  B. Astragalus linifolius is also pollinated, though to a much-lesser degree, by some local species of bees.

  C. The pesticides that control insect herbivores other than grasshoppers are even more toxic to Bombylius flies.

  D. Bombylius flies do not reproduce very fast and their populations do not recover for many years after one spraying of a pesticide that controls grasshoppers.

  E. The populations of some other plant species in the Colorado region have decreased to an even greater extent than the population of Astragalus linifolius since the spraying of pesticides that control grasshoppers first started in the region.

  Correct Answer: D

  Argument construction

  The argument starts with a premise ?Premise 1: Astragalus linifolius (context-setting information: this is a

  rare plant species that is found only in the Colorado region of the United States) reproduces when a

  pollinating agent like a bee or a fly carries the pollen grain from the male part of a plant and deposits it onto

  the female part of another plant of the same species.

  From this premise, it becomes clear that pollinating agents like bees and flies are necessary for the

  reproduction of Astragalus linifolius to take place.

  Next comes the conclusion of the argument: To maintain the population of Astragalus linifolius (a rare

  legume species that is found only in the Colorado region of the United States), the use of pesticides that

  control grasshoppers should be banned in this region.

  This conclusion is followed by two more premises:

  Premise 2 - These pesticides result in significant mortality among the Bombylius flies.

  Premise 3 - Bombylius flies are the most important pollinating agents of Astragalus linifolius.

  Here is how these premises are used to draw the conclusion:

  From Premise 1, we know that Astragalus linifolius cannot reproduce without pollinating agents. From

  Premise 3, we know that Bombylius flies are the most important pollinating agents of Astragalus linifolius.

  By combining Premises 1 and 3, we can draw a subsidiary conclusion that to conserve Astragalus

  linifolius, it's probably important to conserve Bombylius flies too. A decline in the numbers of the latter is

  likely to result in a decline in the numbers of the former.

  When this subsidiary conclusion is combined with Premise 2, we draw the conclusion that to maintain the

  population of Astragalus linifolius, the use of pesticides that control grasshoppers should be banned in that

  region.

  We are looking for the answer choice that provides additional information which makes this conclusion

  stronger than when the above two premises are used alone. Let us analyze the options one by one.

  Answer choices explanation

  [Astragalus linifolius has a short life-span.] This option is incorrect. This argument is concerned with the

  maintenance of population of a particular species. The population of a species would be maintained if its

  death rate and birth rate remain in equilibrium. The life-span of a species is irrelevant to the maintenance

  of its population and, therefore, to this argument.

  [Astragalus linifolius is also pollinated, though to a much-lesser degree, by some local species of bees.]

  This option is incorrect. If there are other pollinating agents through which Astragalus linifolius can

  reproduce, then, assuming that these pollinating agents are not impacted by pesticides that control

  grasshoppers, this plant species might survive even if these pesticides are not banned. Therefore, this

  statement actually weakens the conclusion.

  [The pesticides that control insect herbivores other than grasshoppers are even more toxic to Bombylius

  flies.] This option is incorrect. There may be pesticides that are more toxic to the Bombylius flies than the

  pesticides mentioned in the argument, but this does not strengthen the argument that to save Astragalus

  linifolius, the pesticides that control grasshoppers should be banned. For example, consider the statement

  'to get better health, you should eat less sugar.' This statement is of the same format as the conclusion

  drawn in this argument: To achieve Goal A, do Action X. Does a statement that eating oily foods is even

  worse for your health than eating sugar strengthen the above example statement? It does not.

  [Bombylius flies do not reproduce very fast and their populations ....] This option is correct. Suppose that

  Bombylius flies had been able to reproduce fast. Then, even if one spraying had significantly reduced the

  number of flies in a region from, say, 1000 to a mere 100, their fast breeding would have restored the

  population number to its pre-spraying level pretty soon and so there would probably not have been much adverse impact on the amount of pollination that these flies did for Astragalus linifolius and, therefore, in the population of this plant species. However, this statement tells us that the populations of Bombylius flies do not recover for many years post a pesticide spraying. In those years, therefore, the extent of reproduction of Astragalus linifolius is likely to decline, which in turn, is likely to decrease the population of this plant species.

  [The populations of some other plant species in the Colorado region have decreased ...] This option is incorrect. That other plant species have suffered greater declines than Astragalus linifolius since the spraying of pesticides that control grasshoppers started is irrelevant to the conclusion drawn for how the population of Astragalus linifolius may be maintained.

• Question 326:

  The print circulation of The World Tribune has shown a 40 percent decline in the past two years. However, the traffic on the newspaper's website has increased by 30 percent during the same period. The website contains many news sections and blogs that are not featured in the print newspaper but are the most read pages of the website. Therefore, to maintain its profits, the newspaper has decided to discontinue its still-profitable print edition and to introduce more content on the website that is similar to the exclusive content on the most read pages of the website.

  Which one of the following is an assumption on which the decision of The World Tribune depends?

  A. The print circulation of the newspaper would not have declined further in the near future.

  B. To access the content on the newspaper's website, the readers of the website will be willing to pay a monthly subscription fees that is equal to the revenue that the print edition of the newspaper earned per reader each month.

  C. The print circulation of the newspaper declined in the past two years because the newspaper's website offered more interesting content.

  D. The revenue earned from increased website traffic will not be less than the revenue lost by discontinuing the print edition.

  E. Introducing more content similar to the exclusive content on the most read pages of the website will increase the newspaper's website traffic further.

  Correct Answer: E

  Argument construction

  This argument features two versions/modes in which The World Tribune newspaper is available: the Print

  Mode and the newspaper's website (called the Web Mode henceforth).

  Over the past 2 years:

  The Print Mode's circulation has decreased by 40% - Premise 1

  The Web Mode's traffic has increased by 30% - Premise 2

  The website contains many news sections and blogs that are not featured in the print newspaper but are

  the most read pages of the website. This is Premise 3.

  The Conclusion drawn (= the decision made) by the newspaper from these three premises is that:

  to maintain profits, the newspaper should:

  discontinue the still-profitable Print Mode.

  introduce more exclusive content on the website that is similar to the most read pages of the website.

  When we analyze the premises of this argument, we realize that from Premises 2 and 3, the decision-

  makers at the newspaper have assumed that the increase in the Web Mode's traffic is due to the exclusive

  content that makes for the website's most read pages. It is due to this assumption that they have decided

  to introduce more such content on the Web Mode. It can also be said that these decision-makers believe

  (assume) that because such content led to an increase in the website traffic in the past two years,

  introducing more such content will inevitably increase the website traffic in the future too. That is, they are

  assuming that a past relationship between two metrics (amount of exclusive content that forms the most-

  read pages of the Web Mode, website traffic) that held in the past will hold in the future too.

  Further, the explicit goal of the newspaper is "to maintain its profits." However, the decision that it has

  taken concerns its reach ?because the reach ";circulatio";) of the Print Mode was decreasing while the

  reach ";traffi";) of the Web Mode was increasing, the newspaper decided to kill the still-profitable Print

  Mode and focus solely on the Web Mode and take measures to increase the traffic of the Web Mode

  further. So, one necessary assumption that the decision-makers have made is that the increase in profits

  from increasing the traffic of the Web Mode will at least offset (if not exceed) the loss of profits due to

  closing down the Print Mode.

  

  The decision-makers assume that this decision will enable them to "maintain profits," that is:

  z x + y => z - y x => (Post-decision Increase in profit from Web-Mode) (Post-decision Loss of profit from Print-Mode)

  Therefore, to sum up, the assumptions that have gone into the newspaper's decision are:

  over the past two years, the increase in the Web Mode's traffic was due to the exclusive content that makes for the website's most read pages in the future too, introducing more such content will continue to drive an increase in the Web Mode's traffic (Post-decision Increase in profit from Web-Mode) (Post-decision Loss of profit from Print-Mode)

  In analyzing the options in an assumption question, the Negation Test often comes in handy. Since a necessary assumption is, by definition, vital for the conclusion to be logically valid, we can test an answer choice by deeming it to be false. If, upon doing so, the conclusion no longer holds, this means that the answer choice in question is indeed a necessary assumption.

  Let's analyze each option one by one.

  Answer choices explanation [The print circulation of the newspaper would not have declined further in the near future.] This option is incorrect. Suppose the print circulation of the newspaper would have declined further in the near future. Then, the perception that the Print Mode is a sinking business would be further strengthened and the newspaper's decision to kill the Print Mode would be validated. So, if we Negate this answer choice, the conclusion (= decision made by the newspaper) stands strengthened, instead of being demolished. Therefore, this answer choice fails the Negation Test.

  [To access the content on the newspaper's website, the readers of the website will be willing ...] This option is incorrect. Let the revenue that the print edition of the newspaper earned per reader each month (at the time of the decision) be dollars. Suppose the readers of the newspaper's website are not willing to pay a subscription fees of dollars per month for access to the website content. Does this necessarily mean that the newspaper will not be able to maintain its profits? No. For example, suppose the readers of the website are only willing to pay a monthly subscription fees of dollars. If the number of website readers is more than ten times the number of print-edition readers (which it very well might be, because, from the argument, we only know the percentage changes in readership of the print-edition and the website traffic, and not the actual numbers), then the revenue from the website subscription fees will be greater than the revenue from the print-edition. If the costs of the website are not greater than the costs of the print-edition, then the profits from the website will be greater than the profits that the print-edition earned at the time of the decision. Therefore, negating this answer choice does not necessarily impact the conclusion.

  [The print circulation of the newspaper declined in the past two years...] This option is incorrect. Suppose the print circulation did not decline in the past two years because of the content offered in the Web Mode but due to some other reason. The facts of the case still remain the same ?the print circulation was declining, the Web Mode traffic was increasing, and the newspaper wanted to maintain its profits. So, negating this answer choice has no impact whatsoever on the conclusion drawn.

  [The revenue earned from increased website traffic will not be less than...] This option is incorrect. Suppose the revenue earned from increased website traffic is indeed less than the revenue lost by discontinuing the print edition. However, if the costs incurred by the newspaper for the Web Mode are far lesser than those for the Print Mode, then profits earned by the newspaper for the Web Mode can still be greater than or equal to the profits earned for the Print Mode. Therefore, the conclusion ("to maintain profits," kill the Print Mode and put more of XYZ type of traffic-increasing content on the Web Mode) can still stand. Therefore, this answer choice fails the Negation Test.

  [Introducing more content similar to the exclusive content on the most ...] This option is correct. Suppose that introducing more content similar to the exclusive content on the most read pages of the website will not increase the newspaper's website traffic further. The newspaper had assumed: (More such content --> More Web Traffic --> More Profit from Web-Mode that would at least offset the loss of profit from Print-mode). The negation of this answer choice breaks this chain of assumptions and therefore suggests that the newspaper's decision may not result in greater profit from Web-Mode that would at least offset the loss of profit from Print-Mode. Therefore, the profits of the newspaper may not be maintained. The negation of this answer choice substantially weakens the decision made by the newspaper. Therefore, this answer choice represents a necessary assumption on which this decision depends.

• Question 327:

  The Urban Intelligence Unit publishes an annual Livability Ranking, which ranks 100 American cities for their quality of life based on assessments of urban infrastructure, healthcare, education, crime rates, culture and climate. Yet, this ranking should also consider unemployment rates. After all, if a city is unable to offer work opportunities to a sizeable proportion of its population that needs to work for survival, the quality of life for that proportion would be abysmal. The claim that the Livability Ranking should consider unemployment rates in a city plays which one of the following roles in the argument?

  A. It offers a reason to support the conclusion.

  B. It is an assertion that refutes the conclusion.

  C. It is a principle from which the conclusion is derived.

  D. It is a premise of the argument.

  E. It is a conclusion of the argument.

  Correct Answer: E

  Argument construction The annual Livability Ranking (published by Urban Intelligence Unit) ranks 100 American cities for their quality of life based on assessments of: urban infrastructure healthcare education crime rates culture сlimate. However, this ranking should also consider unemployment rates. Reason - If a city is unable to offer work opportunities to a sizeable proportion of its population that needs to work for survival, the quality of life for that proportion would be abysmal.

  Understanding the role played by the claim

  Let's dissect the argument.

  The first step in analyzing this argument is identifying the conclusion. To do this, let's find the position for which the argument offers support.

  From the first sentence, we know that Rankings are based on quality of life.

  The same sentence lists six factors that are assessed in determining the quality of life.

  The last sentence begins with the phrase 'After all,' which indicates that the statement that follows it is a premise. This premise, simply put, is that high unemployment rate means poor quality of life.

  When we put this sentence in conjunction with the first sentence, we see that the argument is constructed to support the position stated in the second sentence: "… [the Livability] ranking should also consider unemployment rates."

  Thus, the claim "this ranking should also consider unemployment rates" asked about in the question is the conclusion of the argument.

  Let's analyze each option one by one.

  Answer choices explanation

  [It offers a reason to support the conclusion.] This is incorrect. The claim is not an explanation or a reasongiving-statement.

  [It is an assertion that refutes the conclusion.] This is incorrect. The claim does not refute any statement in the argument.

  [It is a principle from which the conclusion is derived.] This is incorrect. The claim does not act as the source (principle) of any further conclusion.

  [It is a premise of the argument.] This is incorrect. As discussed in the 'Argument Construction' section, the premises of the argument are contained in the first and the third sentences of the argument. The claim is not a premise.

  [It is a conclusion of the argument.] This is correct. It is in-line with our discussion in the 'Argument Construction' section.

• Question 328:

  Tony: Most web-pages on the internet have numerous enticing and hard-to-ignore hyperlinks, with each hyperlink leading to further hyperlinks and so on. Regularly falling into this bottomless hole of distracting and mostly trivial information on the internet decreases the ability of heavy internet users to do complex reasoning that requires focus and attention.

  James: A research study has found that heavy internet users did better than infrequent users on tests for focus and attention and also had stronger muscles in the brain areas associated with complex reasoning, which suggests a higher usage of these muscles. The dialogue most strongly supports the claim that Tony and James disagree with each other about whether

  A. focus and attention are necessary to do complex reasoning

  B. most web-pages on the internet require internet users to do complex reasoning

  C. most web-pages on the internet have hard-to-ignore hyperlinks

  D. heavy internet usage decreases a person's ability to do complex reasoning

  E. heavy internet users are more knowledgeable than infrequent internet users

  Correct Answer: D

  Argument construction

  Tony says that most web-pages on the internet have multiple enticing and hard-to-ignore hyperlinks. Each

  of these links leads to further hyperlinks and so on. This chain of 'link 1 leading to link 2 leading to link 3...'

  creates, in Tony's words, a "bottomless hole of distracting and mostly trivial information." He says that

  regularly falling into this hole decreases the ability of heavy internet users to do complex reasoning that

  requires focus and attention.

  James responds by citing a research study that found that heavy internet users did better than infrequent

  users on tests for attention and also had higher levels of activation in the brain areas associated with

  complex reasoning.

  Understanding the point at issue

  We need to understand each person's stance clearly to understand the point at issue.

  Tony's stance essentially is: Heavy internet usage decreases the ability to do complex reasoning that

  requires focus and attention.

  1.

  Prior to declaring this stance, he explains how the internet is full of enticing links that lead you to tons of distracting information.

  2.

  He implies that regularly falling into the temptations of internet would decrease a heavy internet user's attention span and ability to focus, and since these two are required to do complex reasoning, these user's ability to do complex reasoning would decrease. James' stance essentially is: Heavy internet users have better ability to focus and attention and also seem to be more actively doing complex reasoning than infrequent internet users.

  1. He cites a research study's findings to support his claim.

  Therefore, the point at issue between Tony and James is whether heavy internet usage decreases a person's ability to do complex reasoning or not. Tony says 'Yes' and James says 'No.' Let's analyze each option one by one.

  Answer choices explanation

  [focus and attention are necessary to do complex reasoning] This is incorrect. Tony explicitly states that focus and attention are necessary to do complex reasoning. As far as James is concerned, the research finding cited by him shows better 'focus and attention' and also more frequent complex reasoning in heavy internet users. Therefore, James too seems to believe that there is at least a correlation between 'focus and attention' and 'complex reasoning.' Since he does not actively rebut Tony on this matter, this is certainly not a bone of contention ?the point at issue ?between the two.

  [most web-pages on the internet require internet users to do complex reasoning] This is incorrect. Tony implies that most web-pages on the internet offer distracting information. Since he believes that complex reasoning requires focus and attention (the opposites of distraction), he might also believe that most web-pages on the internet do not require users to do complex reasoning. James' argument is that heavy internet users do complex reasoning more frequently than infrequent users. We cannot infer from this that James believes that most web-pages on the internet require such skills. James might believe, for example, that heavy internet users are more likely than infrequent users to visit certain specific web-pages that require users to do complex reasoning. Therefore, we cannot infer whether James supports or opposes this option statement. Since we don't even know for sure what James thinks about it, this option certainly is not the point at issue between him and Tony.

  [most web-pages on the internet have hard-to-ignore hyperlinks] This is incorrect. Tony explicitly supports this statement. However, nothing that Tony says commits him to a particular view on this statement. There is certainly no indication that the two hold opposing views on this matter.

  [heavy internet usage decreases a person's ability to do complex reasoning] This is correct. It is in-line with our discussion in the 'Argument Construction' section.

  [heavy internet users are more knowledgeable than infrequent internet users] This is incorrect. 'Knowledge' and 'information' are two distinct entities. While Tony does seem to imply that heavy internet users access more information on the internet than infrequent users, he does not touch at all the question of how much, if at all, this extra information improves the knowledge of heavy internet users. James is silent on both the relative information consumption and the relative knowledge of heavy and infrequent users. Therefore, it is not possible to deduce the stance of either Tony or James on this option statement.

• Question 329:

  Henry: An average American car driver drives a thousand miles per month. If all American car drivers drove only five miles less daily, their monthly mileage would reduce by 15 percent. Five miles is ten thousand steps, the amount of daily walking recommended by doctors for good health. Therefore, if the government could persuade car drivers to drive five miles less daily and walk that distance instead, the total transport-related carbon emissions in the United States would reduce by 15 percent.

  Bill: Cars are responsible for 30 percent of all transport-related carbon emissions in the United States.

  Bill's response to Henry proceeds by A. refuting an assumption on which Henry's argument relies

  B. discrediting Henry's argument by giving of erroneous information

  C. arguing that the benefit of Henry's hypothetical measure might also be achieved in another way

  D. citing seemingly irrefutable evidence that contradicts one of the stated premises on which Henry's argument depends

  E. providing additional information in support of Henry's argument

  Correct Answer: A

  Argument construction

  Henry tells us that:

  An average American car driver drives a thousand miles per month.

  1. So, if all American car drivers drove only five miles less daily, their monthly mileage would reduce by 15

  percent (5 ?30 = 150 miles = 15% of 1000 miles).

  Five miles is ten thousand steps, the amount of daily walking recommended by doctors for good health.

  Therefore, if the government can persuade car drivers to drive five miles less daily and walk that distance instead, the total transport-related carbon emissions in the United States would reduce by 15 percent.

  Bill responds to Henry by saying that cars are responsible for only 30 percent of all transport-related carbon emissions in the United States.

  Understanding how the argument proceeds Let's dissect the argument.

  When we strip Henry's argument to its essence, it is this:

  'Reducing average monthly mileage of American car owners by 15 percent would reduce the total transport-related carbon emissions in the United States by 15 percent.'

  So, Henry is assuming that only car owners are responsible for transport-related carbon emissions in the United States. In his mind, the formula for transport-related carbon emissions is:

  (Total transport-related carbon emissions per month) = (Average carbon emissions made per car mile) ? (Average monthly miles driven per driver) ?(Number of drivers)

  Note that the right-hand side of this equation would give 'total car-related carbon emissions per month'. Henry assumes that this number is equal to 'total transport-related carbon emissions per month'.

  By pointing out that total car-related carbon emissions are, in fact, only 30 percent of all transport-related carbon emissions in the United States, Bill is telling Henry that his assumption was mistaken. And due to this mistake, Henry's argument is incorrect.

  Let's analyze each option one by one.

  Answer choices explanation [refuting an assumption on which Henry's argument relies] This is correct. It accords with the discussion done in the argument analysis above.

  [discrediting Henry's argument by giving of erroneous information] This is incorrect. We have no reason to decide that the information given by Bill is erroneous.

  [arguing that the benefit of Henry's hypothetical measure might also be achieved in another way] This is incorrect. The benefit of Henry's hypothetical measure is a 15 percent reduction in the total transport-related carbon emissions in the United States. Bill suggests no other way to achieve this benefit.

  [citing seemingly irrefutable evidence that contradicts one of the stated premises on which Henry's argument depends] This is incorrect. The stated premises on which Henry's argument depends are: If all American car drivers drove only five miles less daily, their monthly mileage would reduce by 15 percent. Five miles is ten thousand steps to walk. (The argument also makes use of an unstated premise (that is, an assumption): all transport-related carbon emissions in the United States are made by cars.) Bill's response does not contradict either of the two stated premises listed above. Further, Bill cites evidence that contradicts Henry's claim, not a premise.

  [providing additional information in support of Henry's argument] This is incorrect. As discussed in the analysis section above, Bill's response does not support Henry's argument.

• Question 330:

  As per a report published by the United States Bureau of Economic Analysis, in the last five years, the per capita income of American workers employed in Agriculture and allied services has increased by 10 percent while that of American workers employed in other sectors has increased by 20 percent. Therefore, American workers employed in other sectors now earn a higher per capita income than those employed in Agriculture and allied services.

  The argument's reasoning is questionable because the argument fails to rule out the possibility that

  A. five years ago, fewer American workers were employed in other sectors than in Agriculture and allied services

  B. five years ago, the per capita income of American workers employed in other sectors was significantly less than that of American workers employed in Agriculture and allied services

  C. over the last five years, the number of American workers employed in other sectors has decreased

  D. over the last five years, many American workers who were previously employed in Agriculture and allied services shifted to other sectors

  E. the total national income generated by Agriculture and allied services now is still greater than that generated by other sectors

  Correct Answer: B