What happens when two forces act in the same direction?

AThey cancel each other out.
BThe stronger one prevails.
CTheir strengths are added.
DTheir sum divided by two is the total force.

Verified Answer :

If this is a question regarding vectors, I would say that you are to add the 2 forces, since they are going in the same direction. if they were going opposite directions, you would have to subtract one from the other. this can best be explained from a mechanical physics YouTube video.