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': 'Factor constituting the quality and quantity of pain: \nSelect and explain. \nA. Spontaneity, intensity, duration, B. Character, severity, C. History, location, diagnosis, D. Stimulus, severity', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The three important factors constituting the quality\xa0and quantity of pain are its spontaneity, intensity, and duration', 'role': 'assistant'}]