The answer is cccccccccccccccccccccccccc
Not to good with math but the answer may be B
You would distribute multiply every thing inside the parenthesis by the number on the out side of it on the the left the go to the other side of the addition sign and do the same then combine like terms
The GCF of 3 and 12 is 3, so divide both numbers by 3
3 / 3 = 1
12 / 3 = 4
So in simplest form is 1:4