It Has Been Difficult to Do Double-Blind,placebo-Controlled Studies on the Effects

Multiple Choice

It has been difficult to do double-blind,placebo-controlled studies on the effects of steroids because

A) the federal government will not allow research with controlled substances.
B) they produce detectable psychological effects.
C) the potency of the drugs is so variable from one sample to another.
D) the researchers could face a massive lawsuit.