What Was the Most Significant Reason Why the Psychiatrists in the Beck

What was the most significant reason why the psychiatrists in the Beck et al.(1962) study found it difficult to agree?

A) Some psychiatrists were better at their job than others.
B) The patient did not give the same report to each psychiatrist.
C) Each psychiatrist diagnosed patients according to their own particular theories.
D) Different techniques were used to determine the diagnosis.
E) The diagnostic system did not adequately specify the signs and symptoms for the disorder(s) .