be smaller than Earth. have a source of light inside. have a smoother surface than Earth. have fewer impact craters on the surface.
I gave my students this multiple choice question: A model of the Moon would be different from a model of Earth in that the Moon should

Only one answer is correct among these 4 choices:
- be smaller than Earth.
- have a source of light inside.
- have a smoother surface than Earth.
- have fewer impact craters on the surface.

Could you tell me which one is correct?

be smaller than Earth.