A Comparison of Cognitive-Behavioral Therapy (CBT),behavior Therapy (BT),and Interpersonal Therapy

A comparison of cognitive-behavioral therapy (CBT) ,behavior therapy (BT) ,and interpersonal therapy (IPT) for the treatment of bulimia nervosa indicates that one year after treatment,

A) BT was superior to CBT, which was superior to IPT.
B) BT was equivalent to CBT and both were superior to IPT.
C) CBT was equivalent to IPT and both were superior to BT.
D) all therapies had some effectiveness but no therapy was found to be more effective than any other.