The beginning of the anglo-saxon period roughly corresponds with which historical event?

The correct answer for this question is this one: "C.) the Roman pull-out from Britain." The Romans "hired" the Anglo-Saxons but these Anglo-Saxons became rebels. They stayed while the Britain are pulled out by the Romans.

These are the following choices:
A.) the Norman invasion of Britain
B.) the Viking invasion of Britain
C.) the Roman pull-out from Britain
D.) the Battle of Hastings

I’m just thinking something from the top of my head so it may not be much so if weathering didn’t exist, there wouldn’t be anything to break up earth’s crust naturally. so by assumptions, the rocks on earth would be larger than they actually are since there’s nothing to break them up into smaller parts.overall, i’m not really sure, but all i know is that it’ll mess up the rock cycle that we have now.hoped this .