Peg's parents are both obese. She has dieted at least six times, each time losing a considerable amount of weight and subsequently regaining it. Peg does not exercise. Which of the following is true about Peg's situation?

a) Her frequent yo-yo dieting has likely led to greater amounts of lean body mass.
b) Her problem is genetic and there is no reason for her to attempt to lose weight.
c) When she ends a diet, she likely regains additional body fat.
d) Her problem results from poor habits, but genetics will prevent her from ever losing weight.