What is the prime factorization of 54?
a. 9 • 6
b. 22 • 32
c. 33 • 2
d. 32 • 6

Actually none of them are the prime factors of 54.

A. indeed are factors, but neither of them are prime.
But you can break down A. into prime factors, 9 = 3*3, 6 = 3*2.
So now you have 3*3 * 3*2, which are all prime.
So the prime factorization of 54 is 3*3*3*2