This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'The last case of small pox was repoed in the world \nSelect and explain. \nA. 1977, B. 1978, C. 1979, D. 1982', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The eradication of smallpox was confirmed in April 1977 by an international commission. Reference; Park&;s Textbook of preventive and social medicine, 24th edition.Pg no. 153', 'role': 'assistant'}]