What Is Believed to Be the Cause of the Long,meandering

Multiple Choice

What is believed to be the cause of the long,meandering scarps (cliffs) observed on Mercury?

A) Shrinkage of the planet as Mercury cooled
B) Large impacts near the end of the early period of heavy bombardment
C) Volcanic eruptions along crustal faults over hot spots in the mantle
D) Crustal movement due to convection in the mantle,similar to continental drift on Earth but to a much smaller extent