question_answer

If A, B, C are non-empty sets and \[(A\times B)\cup (B\times A)=C\times C,\] then

A)  \[A=B\,\,but\,A\ne C\]

B)            \[A=C\text{ }but\text{ B}\ne C\]

C)  \[A=B=C\]

D)  A, B, C may be disjoint set also