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

Question

Quizplus · Accepted Answer

Placebos are inactive substances that are given to participants in a study as a control group to compare the effects of the active substance being studied. In this case, the placebo pills do not contain vitamin D, which is the active substance being studied, and are provided to the control group. Therefore, the best choice is A) placebos. Options B), C), and D) are not appropriate in this context.

Researchers Are Conducting a Study to Determine the Effects of Vitamin