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': 'Micro abrasion involves the use of: \nSelect and explain. \nA. Sulphuric acid, B. Acetic acid, C. Phosphoric acid, D. Hydrochloric acid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]