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: Microbiology
[{'content': 'All the following are true about IGRA \n(Interferon gamma release assays) except. \nSelect and explain. \nA. Differentiates active and latent TB, B. Also called quantiferon TB gold assay, C. Alternative to tuberculin skin test, D. Urine is used as sample', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Blood is the sample used in IGRA.', 'role': 'assistant'}]