Answer: Binge-eating disorder
Step-by-step explanation:
According to the situation given the binge eating is the correct option. This is because of the fact that binge eating is a disorder in which the person eat large quantities of food repeatedly after small intervals of time. In this situation the person loss control over itself from eating food. Such a person experience shame, guilt and distress because of abnormal eating habits. The person also takes purging as a measure that is by vomiting or using laxative to gain weight by binge eating. It is the most common eating disorder in United States. Here in the given situation the classmate to avoid weight gain goes to gym.