The correct option is C It depends on learning, the inheritance of knowledge.
"It is part of this unique status that in man a new form of evolution begins, overlying and largely dominating the old, organic evolution which nevertheless also continues in him. This new form of evolution works in the social structure, as the old evolution does in the breeding population structure, and it depends on learning, the inheritance of knowledge, as the old does on physical inheritance." - this extract from the passage supports the claim that while the new form of evolution is associated with social structure and learning and inheritance of knowledge, the old organic form of evolution is associated with breeding structure and physical inheritance. In this context, option C is the best answer.