This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'An immunologist sees a child with a suspected primary immunodeficiency and orders a nitroblue tetrazolium test. What condition is she screening the child for? \nSelect and explain. \nA. Chediak-Higashi syndrome, B. Tuftsin deficiency, C. Chronic granulomatous disease, D. Wiskott-Aldrich syndrome', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Nitroblue tetrazolium test is used as a screening test for Chronic granulomatous disease. In CGD, leukocytes fails to reduce Nitroblue Tetrazolium during phagocytosis(negative result). Positive test result means neutrophils turn blue. Negative test means nitroblue tetrazolium remains yellow. Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition', 'role': 'assistant'}]