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': 'Specificity of a test refers to its ability to detect the following: \nSelect and explain. \nA. True positives, B. True negatives, C. False positives, D. False negatives', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Specificity of a test is defined as the percentage of persons without the disease of interest who have negative test results, i.e., true negatives. Specificity is calculated as follows: Sensitivity is defined as the ability of the test to identify correctly all those who have the disease i.e. true positives. Ref: Greenberg R.S., Daniels S.R., Flanders W.D., Eley J.W., Boring, III J.R. (2005). Chapter 6. Diagnostic Testing. In R.S. Greenberg, S.R. Daniels, W.D. Flanders, J.W. Eley, J.R. Boring, III (Eds), Medical Epidemiology, 4e.', 'role': 'assistant'}]