This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Health education & planning, Subject name: Social & Preventive Medicine
[{'content': 'Health promotion includes \nSelect and explain. \nA. PAP smear, B. Mass treatment, C. Immunization, D. Health education', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ref: 25th Ed K.Park's Textbook Of Preventive and Social Medicine", 'role': 'assistant'}]