Answer:
C
Explanation:
Look at the coefficients in the expression: -3 and 12. The largest number that divides them both is 3. That means you can factor out either a 3 or a negative 3. Try 3.
3(-x - 4) is not on the list of answers. Also, it's unusual to factor out a value that leaves a negative coefficient on x.
Try factoring out -3.
-3(x + 4) is answer choice C.
Bonus
Because this is a multiple-choice question without a "non of these" option, you can solve the problem by expanding--multiplying out--the answers!
A. 3(x + 4) = 3x + 12 ...nope, not it
B. 3(x - 4) = 3x -12 ...nope, not it
C. -3(x + 4) = -3x -12 ...bingo!