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': 'One of them is NOT a principle of health education: \nSelect and explain. \nA. Credibility, B. Feedback, C. Setting an example, D. Utilization', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]