This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
[{'content': 'Excessive eating followed by purging using laxatives in 20 years old females: \nSelect and explain. \nA. Bulimia nervosa, B. Anorexia nervosa, C. Binge eating disorder, D. Schizoprenia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Bulimia Nervosa', 'role': 'assistant'}]