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': 'According to modified plan of operation, endemic areas were classified based on \nSelect and explain. \nA. API, B. ABER, C. Slide positivity rate, D. Slide falciparum rate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]