This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Microbiology
[{'content': 'Which one of the following is diagnosed by latex agglutination for antigen in CSF? \nSelect and explain. \nA. Cryptococcus, B. Aspergillosis, C. Candida, D. Histoplasmosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) Cryptococcus # Approximately 90% of patients with cryptococcal meningoencephalitis, including all those with a positive CSF smear, have capsular antigen detectable in CSF or serum by latex agglutination.# Certain important points about cryptococcus> Cryptococcus is the only pathogenic yeast> It is characterized by a prominent polysaccharide capsule, which stands out in Indian ink preparation> Features which are seen in only in pathogenic cryptococci are Ability to grow at 37degC Ability to hydrolyse urea', 'role': 'assistant'}]