Researchers are conducting a study to determine the effects of zinc supplements on the human immune system.The study involves providing pills that contain zinc to one group of human subjects and pills that do not contain zinc or other active ingredients to another group of people.The pills that do not contain zinc are
A)placebos.
B)probiotics.
C)antidotes.
D)supplements.

Question

Quizplus · Accepted Answer

Pills that do not contain the active ingredient being studied but are given to study participants with the intention of creating a psychological response are called placebos. In this case, the pills that do not contain zinc are being used as placebos to control for the psychological effects of taking a pill, such as the placebo effect.

Researchers Are Conducting a Study to Determine the Effects of Zinc