The Rate of Cratering in the Lunar Highlands Shows Us

The rate of cratering in the lunar highlands shows us that

A) the largest impacts are the youngest, such as Copernicus and Tycho.
B) most of the asteroids must have hit the Moon, not the Earth.
C) they must be younger than the older, darker mare.
D) the oldest rocks are at least as old as the mare, but some craters are much younger.
E) they range from 4.6 - 4.4 billion years old, on average.