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': 'A 50-year-old obese man with hyperlipidemia, hypertension, and type 2 diabetes mellitus comes to the physician for a routine examination During the visit he asks, “What is my risk of having a heart attack?” \n\nWhile searching your information database, which of the following represents the best study design to address his question? \nSelect and explain. \nA. Case-control study, B. Case series, C. Cohort study, D. Cross-sectional study', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]