This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammatory Bowel Disease, Subject name: Medicine
[{'content': 'Treatment of choice in intractable ulcerative colitis ; \nSelect and explain. \nA. Mucosal proctectomy - Ileoanal pouch anastomosis, B. Proctectomy, C. Colectomy with ileostomy, D. Ileorectal anastomosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Indications for surgery in ulcerative colitis Intractable disease Fulminant disease Toxic megacolon Colonic perforation Massive colonic hemorrhage Extracolonic disease Colonic obstruction Colon cancer prophylaxis Colon dysplasia or cancer', 'role': 'assistant'}]