This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of health and disease, Subject name: Social & Preventive Medicine
[{'content': 'Where was the last case of Smallpox occured? \nSelect and explain. \nA. Somalia, B. Libya, C. Sudan, D. Uganda', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The last naturally occurring case was diagnosed in October 1977 in Somalia and the World Health Organization ceified the global eradication of the disease in 1980.', 'role': 'assistant'}]