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: Surgery
[{'content': 'Which does not contribute to Enterobillary Fistula - \nSelect and explain. \nA. Duodenal ulcer, B. Gall stones, C. Gastric ulcer, D. Carcinoma gall bladder', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]