Please please answer I really need help <3

I’ll give you BRAINIEST :((

Match each disease with the body system it affects

In a study of a weight loss program, 40 subjects lost a mean of 3.0 lb after 12 months. does the weight loss program have practical significance? a. yes, because the weight loss program worked and the subjects lost a mean of 3.0 lb. b. no, because the mean weight loss of 3.0 lb after one year does not seem to justify the program. c. no, because the sample of 40 subjects was too small to determine if the program was useful. d. yes, because the mean weight loss of 3.0 lb after one year does seems to justify the program.

How could you find out if that advice is based in scientific evidence?