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': 'Most common cause of pulp pathology is: \nSelect and explain. \nA. Microbes, B. Trauma, C. Leakage from filling materials, D. Pressure sensation from condensation of filling materials', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]