Which expression is equal to (32)(8)(5x) using the associative property?

Seeing as there are no answer choices, here are all the answers I would think to make. Quick note, associative property of multiplication states that you can change the parenthesis/order of your multiplication in any order and it will stay true, example: (5)(8)(3)=40*3 and 24*5.
Answers: (32)(40)(x), (32)(40x), (32)(8)(5)(x), (32)(8x)(5), (160)(8x), (160x)(8), (160)(8)(x), (32x)(8)(5), (256x)(5), (256)(5x), (256)(5)(x), (1280)(x), (1280x)

These are the multiples of 15 but what you are probably asking or what are the factors of 15