Although Cara has been obese for as long as she can remember, she is determined to lose excess body weight with a low-calorie diet. Cara is most likely to have difficulty becoming and staying thin because .
a. muscle tissue is maintained by fewer calories than is fat tissue.
b. low-calorie diets trigger increased secretions of PYY.
c. her resting metabolic rate will increase and prompt her to overeat.
d. if her body perceives starvation it will adapt and burn fewer calories.
e. she may have a higher-than-average set point for body weight.