A team of researchers conduct an experiment to test the effectiveness of a new drug in treating anxiety disorders. The participants in the control group receive sugar pills without active ingredients, while those in the experimental group receive the new, anti-anxiety drug. In this example, the researchers use a:

A. double-blind procedure. B. correlation coefficient. C. placebo. D. single-blind procedure.

Answer: C) placebo

Explanation: In this experiment, the researchers used a placebo because neither the control group nor the experimental group knew if they were taking the real drug or the sugar pill without active ingredient.

A placebo is simply a medical or clinical procedure which is meant to trick participates in a clinical experiment that they are been given the trial drugs where as it was just a pills made from inactive ingredients, sometimes it has physical effects on the participants although these effects are more of a psychological phenomenon.