\begin { gather* } Set A = \{ x|x = prime number\} \\ Set B = \{ x|x = 2n + 1, n = positive integer\} \end { gather* }  Which of the following is an element of both set \(A\) and \(B\) shown above?
(A)2 (B)9 (C)13 (D)15 (E)33
C