1. describe what a person would need to do in terms of caloric input and output to: lose weight: gain weight:

The correct relationship between calories and weight loss or gain is:

Explanation:

Calories are the energy used by the body to perform different activities, however, when the intake of calories exceeds the energy that the body needs, it accumulates as fat or muscle within the body increasing body weight, this is denoted in fact that each gram of protein contributes about 4 calories while each gram of protein contributes about 9 calories, for this reason, people who prefer fatty foods are more likely to suffer from obesity, since the amount of calories they eat with each food is much greater, meanwhile, people who want to reduce their weight regularly consume foods low in calories or lean, in order to provide their body with only the amount of energy it requires.