The correct option is B 6, 12, 18, 24, 30...
Factor: A factor divides a number completely without leaving any remainder.
So factors of 6 are 1, 2, 3, and 6 which divides the number 6 without leaving any remainder.
Multiples: A multiple is the product that we get when one number is multiplied by another number.
6 × 2 = 12, here 12 is a multiple of 6
Thus multiple of 6 are 6, 12, 18, 24, 30...