The GCF we factor out is 4a
8ab = 4a*2b
16ac = 4a*4c
12a = 4a*3
Each term has been factored so that 4a is a factor
Using those factorizations, we can use the distributive property in reverse
8ab - 16ac + 12a = 4a*2b - 4a*4c + 4a*3
8ab - 16ac + 12a = 4a*(2b - 4c + 3)
Answer is choice A
