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': 'For assessing new disease with no etiological hypothesis which is the best study \nSelect and explain. \nA. Cohort study, B. Case control study, C. Randomised control trial, D. Descriptive epidemiology', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]