The skill of dividing history into eras based on important features is called..

D

Explanation:

"Periodization is the process or study of categorizing the past into discrete, quantified named blocks of time"

For this reason I think that it is D

“the battle of stalingrad is not a turning point necessarily in strategic terms, because a lot more has to be done before the soviets can be certain of defeating germany,” says renowned world war ii historian richard overy. the germans had fought nearly a thousand miles across the soviet union to get to stalingrad.

when arthor pulls out the sword

explanation:

becase he becomes !