What Do the Surviving Works of the Greek Historian Polybius

What do the surviving works of the Greek historian Polybius demonstrate?

A) He followed Thucydides in seeking rational motives for historical events.
B) He focused on the growth of the Greek city-states from their origins to their collapse.
C) Ancient historians continued to fail to find accurate, firsthand sources.
D) He relied on the models of Herodotus and ascribed historical change to the intervention of gods.
E) He used oral sources and myth to supplement non-written documents.