Lisa complains that she has a slow metabolism, but it’s her fault because people can’t control how quickly their metabolism works

There are a number of factors that can determine a person’s metabolic rate: (1) Body size and composition- having more muscle mass can make a person burn more calories. (2) Gender- men have less body fat and more muscle mass, which means they burn calories faster. (3) Age- the older a person gets, the more muscle mass decreases, which slows down the burning of calories. There is nothing much that can be done in slowing down one’s metabolism. A person can only control the number of calories burned through physical activity.

answer: the first option is not an affect of aging. so the first option is the answer. (secondary sex characteristics appear)