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': 'Dependency ratio includes - \nSelect and explain. \nA. Less than 15 years, B. Less than 85 years, C. 30-50 years, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Numerator in dependency ratio is age group less than 15 years (0-14 years) and more than 65 years.', 'role': 'assistant'}]