If X and Y are two sets, then x ∩ (Y ∪ X)' equals

X Y $\phi$ None of these

$\phi$

We have, $X \cap(Y \cup X)'=X \cap\left(Y' \cap X'\right) \cap Y'=\left(X \cap X'\right) \cap Y'=\phi \cap Y'=\phi$ Hence (3) is the correct answer.