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
Most common organism causing meningitis in patients with CSF leak - 
Select and explain. 
A. Pneumococcus, B. H. influenzae, C. Staphylococcus, D. E.coli
A: Pneumococcus
Answer: A: Pneumococcus 
Explanation: None