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: Medicine
[{'content': 'In an old patient, the best indicator of probability of developing cardiovascular disease can be calculated by- \nSelect and explain. \nA. LDL/HDL ratio, B. Triglycerides, C. Total cholesterol, D. Serum LDL', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]