This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Screening, Subject name: Social & Preventive Medicine
[{'content': 'Sensitivity is \nSelect and explain. \nA. True positive\\/ true positive + false negative, B. True negative\\/ false positive + true negative, C. True negative\\/ true negative + false positive, D. True negative\\/ false negative + true positive', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Repeated question', 'role': 'assistant'}]