2. In a study examining the effects of CCK on eating, fasting participants are randomly assigned to get either an injection of CCK or a saline injection.

Thirty minutes after the injections, all participants are allowed to eat as much ice cream as they want.

The results show that both groups eat the same amount of ice cream. This piece of research is an example of a ________ and it ____________ previous research on the role that CCK plays in hunger and eating.

a. true experiment; supports

b. true experiment; contradicts

c. correlational study; supports

d. correlational study; contradicts