Which of the following could be an example of balanced forces acting on an object (net force $F_{\mathrm{net}}=0$)?

• A. A hockey puck speeding up on ice because a player applies a forward force greater than friction
• B. A cart being pulled to the right with constant pull while no other horizontal forces act
• C. A book resting on a table, with the normal force upward equal in magnitude to the gravitational force downward
• D. A skydiver just after jumping, when gravity is greater than air resistance

Answer: (C)