The correct option is A If A ⊂ B and A ≠ B, then A is called superset of B.
We can see that all the three options viz., option A, B, and C are true by the definition of subsets.
Now, if A and B are two non-empty sets and A ⊂ B and A ≠ B, then A is called the proper subset of set B, and B is called the superset of set A.
Therefore, option D is not true and hence it is the only correct option out of the given options.