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: Radiology
[{'content': "'Scalloping' of the edge of sigmoid colon on barium enema seen in: \nSelect and explain. \nA. Diveiculosis, B. Ulcerative colitis, C. Carcinoma colon, D. Pneumatosis intestinalis", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. Pneumatosis intestinalis', 'role': 'assistant'}]