Answer:
I would pick the last option. Sorry if I am wrong
Step-by-step explanation:
1. 6(a+2) Multiply the 6 by a and the 6 by 2
(6a+12)
2. 6a+12 You can leave this one alone
3. 3(2a+4) Multiply 3 by 2a and 3 by 4
