If the reaction force is the ground pushing against the feet of the runner. , identify the action force in the example.

Responses
A The runner pushing against the air.The runner pushing against the air.
B The wind pushing the runner's face.The wind pushing the runner's face.
C The runner's feet pushing against the ground.The runner's feet pushing against the ground.
D The ground pushing against the feet of the runner.

C The runner's feet pushing against the ground.