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

Question

Quizplus · Accepted Answer

Pills that do not contain the active ingredient being studied are typically referred to as placebos. Placebos are used as a control group in studies to compare the effects of the active ingredient against those of a placebo. Supplements and probiotics are types of active ingredients that can be included in pills. Antidotes are substances used to counteract the effects of toxins and overdoses and are not relevant to this study.

Researchers Are Conducting a Study to Determine the Effects of Vitamin