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: Social & Preventive Medicine
[{'content': 'World health day – \nSelect and explain. \nA. 7th april, B. 7th July, C. 7th Dec., D. 7th Feb', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]