Which of the following statement is NOT correct about find operation?

(A) It is not a requirement that a find operation returns any specific name, just that finds on two elements return the same answer if and only if they are in the same set
(B) One idea might be to use a tree to represent each set, since each element in a tree has the same root, thus the root can be used to name the set
(C) Initially each set contains one element
(D) Initially each set contains one element and it does not make sense to make a tree of one node only