Answer:
Should be : The Ball Pushing On The Person
Explanation:
while the Air resistance answers have a point this question is asking about the reaction and the only reaction answer is the ball pushing on the person. every action has a reaction,
The ball wants to stay still so it pushes back on the person with all it's force, but the person pushes the ball with more force then the ball has so the ball rolls.
(may have explained it to much or weirdly sorry)