The choices below describe four hypothetical planets. Which one's surface would you expect to be most crowded with impact craters? (Assume the planets orbit a star just like the Sun and that they are all the same age as the planets in our solar system.)

Question

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The closer a planet is to the Sun, the more impact it receives from asteroids and debris. The slower the rotation, the more time a given area of the planet spends facing the direction of the incoming debris, which means more impacts over time. Therefore, a hypothetical planet with the size of the Moon (A) and the distance from the Sun of Mars, which is closer than Earth, but with a slow rotation, is expected to have the most impact craters on its surface.

The Choices Below Describe Four Hypothetical Planets