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': 'The best measure of burden of disease in a defined population is \nSelect and explain. \nA. DALY - Disability Adjusted Life Years, B. QALY - Quality Adjusted Life Years, C. HATE - Health Adjusted Life Expectancy, D. DFLE - Disability Free Life Expectancy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]