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': 'Which of the following causes most damage to the protective layer of the tooth: \nSelect and explain. \nA. Intrusion, B. Extrusion., C. Lateral luxation., D. Concussion.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]