The last one x^4.
A: If you bring 2^-5 to the numerator which is what the - expects you to do, then you get x^5 which is 32
B: No problem here. 32 = 32
C: 2^1 * 2^4 = 2^(1 + 4) = 2^5.
C: 2^5 is 32
D: 2^4 = 16.
Answer: D does not agree with the others.
