The power set of a set with \( n \) elements contains \( 2^n \) elements. This is because each element of the set can either be included or excluded from a subset.
Given that the set \( A \) contains 15 elements, the number of subsets (or elements in the power set) is:
\[
2^{15}
\]
Thus, the correct answer is \( 2^{15} \).