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: Dental
[{'content': 'Hypochlorite does not cause \nSelect and explain. \nA. Bleaching, B. remove smear layer, C. Lubricating, D. Flush out debris', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]