This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
[{'content': 'Specificity of a screening test measures \nSelect and explain. \nA. False positives, B. True positives, C. False negatives, D. True negatives', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Specificity in the above image = d/(b+d)x100 Specificity is defined as the ability of a test to identify correctly those who do not have the disease, that is, "true-negatives". Ref: 25th edition, Park\'s Textbook of Preventive and Social Medicine, Page no. 152', 'role': 'assistant'}]