eruptions of active volcanoes the impacts of many meteoroids shifting rock on the Moon's surface ("moonquakes") tidal forces caused by the Earth and Sun
I gave my students this multiple choice question: The surface of the Moon is covered with craters. Most of these craters were formed by

Only one answer is correct among these 4 choices:
- eruptions of active volcanoes
- the impacts of many meteoroids
- shifting rock on the Moon's surface ("moonquakes")
- tidal forces caused by the Earth and Sun

Could you tell me which one is correct?

the impacts of many meteoroids