Explanation: C: If you are adding nodes to a multiple-node cluster, more than half of the existing nodes in the cluster must be healthy (indicated by cluster show).
E: If you are adding nodes to a two-node switchless cluster, you must have installed and configured the cluster management and interconnect switches before adding additional nodes.
Incorrect:
not A: If you are adding a second node to a single-node cluster, the second node must be installed, and the cluster network must be configured. Not D: The switchless cluster functionality is supported only in a two-node cluster.
References:
Adding nodes to the cluster (https://library.netapp.com/ecmdocs/ECMP1636037/html/GUID-B13FF812-785E-4E62-9914-30E7A8F51A4C.html)