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': "Technique used to remove superficial stains: \nSelect and explain. \nA. Macro abrasion, B. Micro abrasion, C. Superoxol, D. Mc inn's solution", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]