Michael Performed an Experiment on Police Officers to Determine the Relationship

Multiple Choice

Michael performed an experiment on police officers to determine the relationship between exercise and stress.One police department's officers performed 30 minutes of exercise at the beginning of their shift,while another department's officers did not.The department who did not take part in an exercise program is known as the

A) independent variable.
B) experimental group.
C) pretest.
D) control group.
E) posttest