What is the MOST likely cause of the smooth and relatively crater-free surfaces of lunar maria?
A) Volcanic ash rained on the surfaces of the basins in recent geological times, covering previous craters.
B) The lava in these basins flowed in the relatively late geological history of the Moon, after the period of major bombardment.
C) Dust storms had eroded and smoothed the surface earlier in the Moon's history.
D) Smoother sediments were left behind after water had flowed into the basins and evaporated away.

Question

Quizplus · Accepted Answer

The lava in these basins flowed relatively late in the Moon's geological history, after the period of major bombardment, filling in older craters and creating the smooth, dark plains we see today.

What Is the MOST Likely Cause of the Smooth and Relatively