\textbf{126-} Let $U = A \cup B$ be the universal set and $C = (A - B) \cup (B - A)$. If $C = B$ and $((A' - B)' \cap C)' = B$, which statement is correct?
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(1) $B \subseteq A$ \hfill (2) $A \cap B = \varnothing$ \hfill (3) $A \subseteq B$ \hfill (4) $A - B$
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