A Team of Researchers Conduct an Experiment to Test the Effectiveness

Multiple Choice

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.