A rock rests on the ground. A force pulls the rock toward the earth, and another force pulls the rock toward the moon. Which statement best explains why the rock stays on the ground?

Only one force can act on an object at one time.

The rock is moving, but it's not visible to the human eye.

The force pulling the rock toward the earth is greater than the force pulling the rock toward the moon.

The force pulling the rock toward the earth is weaker than the force pulling the rock toward the moon.