This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Human Immunodeficiency Virus, Subject name: Microbiology
The most common organism amongst the following that causes acute meningitis in an AIDS patient is a: 
Select and explain. 
A. Streptococcus pneumoniae, B. Streptococcus agalactiae, C. Cryptococcus neoformans, D. Listeria monocytogenes
C: Cryptococcus neoformans
Answer: C: Cryptococcus neoformans 
Explanation: Ans. is 'c' i.e., Cryptococcus neoformans(Ref: Harrison, 18th/e, p. 1559, 1560; 17th/e, p. 1182)* Most common cause of seizures - Toxoplasma* Most common cause of meningitis - Cryptococcus* Most common cause of focal neurological deficit - Toxoplasma