the force of gravity the force of friction the force of magnetism the force of the student's push
I gave my students this multiple choice question: A student sets a block at the top of a wooden ramp. The student pushes the block. As the block slides down the ramp, it slows down and then comes to a stop. What force causes the block to slow down?

Only one answer is correct among these 4 choices:
- the force of gravity
- the force of friction
- the force of magnetism
- the force of the student's push

Could you tell me which one is correct?

the force of friction