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': 'H. pylori infection causes carcinoma by which mechanism- \nSelect and explain. \nA. Production of nitrosamines, B. Gastric metaplasia, C. Increasing acid secretion, D. Causing mutation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]