This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal Radiology, Subject name: Radiology
[{'content': 'Collar button sign is associated with \nSelect and explain. \nA. Ulcerative colitis, B. Hirshsprung disease, C. Plummer Vinson syndrome, D. Chiladiti syndrome', 'role': 'user'}, {'content': 'Answer: A \nExplanation: "Collar button ulcers" are manifestations of inflammatory processes within the bowel, seen with Ulcerative colitis.', 'role': 'assistant'}]