Choose the One Alternative That Best Completes the Statement or Answers

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
-Given that $P ( A ) = 0.56$ and $P ( B ) = 0.26$ , find $P ( A \cup B )$ if $A$ and $B$ are mutually exclusive.

A) $0.6744$
B) $0.1456$
C) $0.82$
D) 0