In a Comprehensive Meta-Analysis on Psychotherapy for Depression,Robinson Et Al

In a comprehensive meta-analysis on psychotherapy for depression,Robinson et al.(1990) found that:

A) cognitive and cognitive-behavioral therapies were superior to other forms of therapy.
B) cognitive therapy was superior to cognitive-behavioral therapy.
C) cognitive and cognitive behavioral therapy was comparable in success to other forms of therapy once investigator allegiance was controlled.
D) cognitive and cognitive-behavioral therapy was less effective than behavioral therapy alone.