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': 'The capsule of cryptococcus neoformans in a CSF sample is best seen by - \nSelect and explain. \nA. Gram stain, B. India ink preparation, C. Giemsa stain, D. Methenamine-silver stain', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Cryptococcus is the capsulated yeast.\nAmong the given staining techniques, India ink preparation is the best staining technique used for demonstration of\xa0capsule (negative staining) - sensitivity of the technique: 60–75%.\n\nOther capsular staining techniques are:\n\n10% Nigrosin staining\nModified India ink preparation with 2% chromium mercury\nAlcian blue staining\n\nMethanamine silver and Periodic acid- Schiff – used for tissue sample.\nSensitivity of various diagnostic tests- Harrison 18/e p1652\n\nCryptococcal antigen detection in CSF—90%\nBlood culture: 10—30% in non-HIV patients and 60% in HIV patients\nSputum culture: 10%\nSputum antigen detection: 30%', 'role': 'assistant'}]