This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Health care of community & international health, Subject name: Social & Preventive Medicine
[{'content': 'World Anti Tobacco Day is observed on \nSelect and explain. \nA. 31st May, B. 5th June, C. 12th July, D. 24th November', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ref: 25th Ed K.Park's Textbook Of Preventive and Social Medicine", 'role': 'assistant'}]