Find the greatest common factor of 12a^3c and 15ab^3

The greatest common factor of 12 and 15 should be 3 since the only factors of 15 are 1,3,5,and 15 and 3 is the only factor that 15 shares with 12

the correct answer is d

hope this

we can't see all full 4 options, but if this is the full option, than the very left one is correct:

-2/5 * -3 3/4

remake the question, adding a picture of all the question, or write down the full left and right answers.