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': 'What complication commonly occurs in anterior duodenal ulcer - \nSelect and explain. \nA. Bleeding, B. Penetration, C. Perforation, D. Stricture formation', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]