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: Medicine
[{'content': "A young girl presents with abdominal pain and a recent change in bowel habit, with passage of mucus in stool. There is no associated blood in stool and symptoms are increased with stress. The most likely diagnosis is - \nSelect and explain. \nA. Irritable bowel syndrome, B. Ulcerative colitis, C. Crohn's disease, D. Amebiasis", 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]