The Major Limitation of the Works of the Classical Greek

The major limitation of the works of the classical Greek philosophers to an understanding of human behaviour is that:

A) the works tended to underestimate the role of nature in determining human behaviour.
B) the forces that govern human behaviour have changed considerably since their time.
C) the works tended to underestimate the role of nurture in shaping human behaviour.
D) these philosophers did not develop ways to test their theories.