This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Screening for Disease, Subject name: Social & Preventive Medicine
[{'content': 'Specificity measures:(1997) \nSelect and explain. \nA. True negatives, B. False positives, C. True positives, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: aRef: Park, 17th ed, p. 112 & 18,h ed, p. 117', 'role': 'assistant'}]