What is the most likely cause of the smooth and relatively crater-free surfaces of lunar maria?
A) Volcanic ash that rained on the surfaces of the basins in recent geological times
B) Dust storms that eroded and smoothed the surface
C) Sediments left behind after water flowed into the basins and evaporated
D) Lava flows relatively late in the geological history of the Moon

Question

Quizplus · Accepted Answer

The smooth and relatively crater-free surfaces of lunar maria suggest that they were formed by lava flows relatively late in the geological history of the Moon, after the heavy bombardment period had ended. The lava flows covered up the pre-existing craters and created the smooth plains that we see today.

What Is the Most Likely Cause of the Smooth and Relatively