Which expression is equivalent to 9 + 8?
A. 3 to the power of 3 + 2 to the power of 4
B. 3 to the power of 2 + 2 to the power of 3
C. 3 to the power of 2 + 2 to the power of 3
D. 3 to the power of 3 + 2 to the power of 3