James is riding a bike down a hill. As he gets to the bottom, he applies the brakes to stop the
brakes forward motion. Which of the following statements best describes an example of
friction acting on the bicycle?

A. The ground pushing up on the bike
B. James is hands squeezing the handle of the brakes
C. James is body pressing down on the seat of the bike
D. The surface of the brake rubbing the rim of the front tire