Gerard Conducts a Study to Examine the Effectiveness of an Exercise

Multiple Choice

Gerard conducts a study to examine the effectiveness of an exercise program on obese people. The participants must exercise for one hour every day for six months. By the end of the fourth month, Gerard finds that 75 percent of the participants dropped out of the study. What kind of problem has Gerard encountered in his study?

A) Maturation
B) Morbidity
C) Attrition
D) Selection