What Was the Main Idea at the Center of What

What was the main idea at the center of what became known as reform Darwinism?

A) Humans, like animals, lack minds capable of bringing social change on their own.
B) The government should remain uninvolved in both education and social work.
C) Cooperation, rather than competition, would best promote human progress.
D) The possibility of reform rests entirely with evolutionary forces.
E) For society to truly reform, any "imitation" of welfare must cease.