What Is So Significant About the Recent Fossil Finds of an H

What is so significant about the recent fossil finds of an H. erectus and an H. habilis from Ileret, Kenya, east of Lake Turkana?

A) They prove that H. erectus and H. habilis coexisted in the same ecological niche and eventually interbred to result in a single species.
B) They prove that functional differentiation in toolmaking preceded the advent of Homo.
C) They prove that sexual dimorphism was finally absent as a trend in human evolution by 2 m.y.a.
D) They negate the conventional view held since 1960 that habilis and erectus evolved one after the other. Instead, they lived side by side in eastern Africa for perhaps half a million years.
E) They confirm that H. habilis evolved from H. erectus.