If a Patient with Major Depressive Disorder Improves When Given

If a patient with major depressive disorder improves when given a placebo,then…

A) the patient should still be switched to an antidepressant drug.
B) patients are likely to receive medical treatment outside of the clinical study.
C) patients likely did not have major depressive disorder.
D) other conditions, such as meeting with clinical staff, must have led to reduced depressive symptoms.