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': 'Sensitivity is: \nSelect and explain. \nA. True positive/True positive + false negative, B. Truerositive/False positive + true negative, C. True negative/True negative + false positive, D. True negative/False negative + true positive', 'role': 'user'}, {'content': 'Answer: A \nExplanation: True positive/True positive + false negative', 'role': 'assistant'}]