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': 'The health promotional phase in public health is between\nthe years: \nSelect and explain. \nA. 1880-1920, B. 1920-1960, C. 1960-1980, D. 1981-2K', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Disease control phase: 1880 - 1920\nHealth promotional phase: 1920 - 1960\nSocial engineering phase: 1960 - 1980\nHealth for all phase: 1981-2000\n\nEssentials of preventive and community dentistry\xa0\nSoben Peter\xa0\n5th edition', 'role': 'assistant'}]