These powers are small enough that you could calculate (or approximate) each one and compare
D is incorrect.

Try expanding every exponent into the underlying multiplication (for example, 2^4 = 2x2x2x2) and see if you can figure out the correct answer.
2^4 * 2 = 2^4 * 2^1

2^4 * 2^1 = 2^(4+1)

2^(4+1) = 2^5