The student uses marbles to represent the planets. She drops a large marble on the plastic sheet. It moves to the middle. Then she drops a smaller marble on the plastic sheet. It rolls toward the larger marble. What larger concept does the student's model best illustrate? A.
Gravity governs the movement of the planets in space, much like the marbles in the model.

B.
A planet at rest will remain at rest because of its inertia, much like the marbles in the model.

C.
Magnetism determines the curved paths of the planets in space, much like the marbles in the model.

D.
The force of a planet in motion depends on its mass and acceleration, much like the marbles in the model.