1.68

(1 pts.) In order to evaluate the effectiveness of a new psychotherapeutic technique, Dr. Schwartz is testing the therapy on clients that have sought treatment from him at his private practice. According to Martin Sen, Dr. Schwartz is conducting an

A) epidemiological study.
B) empirical study.
C) efficacy study.
D) effectiveness study.
(my answer is "D) effectiveness study.") am i right?