Men's and Women's Marathon Records Have Become Both Faster and Closer

Men's and women's marathon records have become both faster and closer together over time.This provides evidence for which of the following statements?

A) Only social factors determine sex differences.
B) The biology of men's and women's bodies are evolving in different ways.
C) The athletic ability of female bodies has been shaped to a large extent by social context.
D) Marathon records are a measure of the real physical differences between male and female bodies.