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': "String sign is a radiological feature of - \nSelect and explain. \nA. Crohn's disease, B. Ulcerative colitis, C. Ileocecal tuberculosis, D. Ischemic colitis", 'role': 'user'}, {'content': "Answer: C \nExplanation: String sign → Congenital hypertrophic pyloric stenosis, Ileocecal tuberculosis.\nString sign of Kantor → Crohn's disease\nString of bead sign → Small bowel obstruction", 'role': 'assistant'}]