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': 'The same screening test is applied to two comuunities X and Y; Y shows more false +ve cases as compared to X. The possibility is: \nSelect and explain. \nA. High sensitivity, B. High specificity, C. Y community has high prevalence, D. Y community has low prevalence', 'role': 'user'}, {'content': "Answer: D \nExplanation: The number of false positives will be more, when the prevalence is less because, the predictive value of a test and hence its ability to identify the true positive is decreased. Therefore Y shows more false positives because the prevalence of disease in question in Y community is low. Ref: Park's Textbook of Preventive and Social Medicine By K. Park, 19th Edition, Page 119", 'role': 'assistant'}]