This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Streptococci, Subject name: Microbiology
Which one of the following organisms is the most frequent cause of acute pyogenic meningitis in adults: 
Select and explain. 
A. Streptococcus pneumoniae, B. Neisseria meningitis, C. Haemophilus influenza, D. Listeria monocytogenes
A: Streptococcus pneumoniae
Answer: A: Streptococcus pneumoniae 
Explanation: Ans. (a) Streptococcus pneumoniaeRef: Dhingra 5th ed. /61y 81