A researcher is interested in the well-being of those elderly who exercise and those who do not. He measures 50 subjects that range in age from 50-60 years old, 25 of which are told to take a walk a day and 25 of which are told not to take walks. The researcher takes blood pressure and stress hormone samples to measure well-being at one time point.
B) Is the study correlational or experimental? How do you know?