Evidence That Obesity Is Influenced by Factors in Addition to Genetics

Evidence that obesity is influenced by factors in addition to genetics includes the fact that

A) mice injected with daily doses of leptin become less active and gain weight.
B) people lose a pound of weight for every reduction of 3500 calories in their diet.
C) the weights of adopted people are highly correlated with the weights of their adoptive parents.
D) the average American weighs more today than did the average American 50 years ago.