Dr. whittaker is a psychotherapist who tells each of his patients the following: "you think that you're unhappy because of all the dreadful things that have happened to you. i'm here to show you that your unhappiness is really due to your thinking that all the things that have happened to you are dreadful! " based on this statement, which type of psychotherapy does dr. whittaker practice?
a) cognitive therapy
b) psychoanalytic psychotherapy
c) behavior therapy
d) humanistic therapy