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': 'People living in developing countries - \nSelect and explain. \nA. 90%, B. 80%, C. 70%, D. 60%', 'role': 'user'}, {'content': "Answer: B \nExplanation: About three fourths of world's population lives in the developing countries.\n95% of growth of population is occurring in developing countries.\nChina is most populous country in the world.\nIndia is 2nd most populous country in the world (17.5% of world's population).", 'role': 'assistant'}]