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
Devi, a 28 year female, has diarrhea, confusion high grade fever with bilateral pneumonitis. The diagnosis is - 
Select and explain. 
A. Legionella, B. Neisseria meningitidis, C. Streptococcus pneumoniae, D. H. influenzae
A: Legionella
Answer: A: Legionella 
Explanation: Atypical Pneumonia– 4th MC cause of community-acquired pneumonia (CAP)
1st three cause of CAP are Streptococcus pneumoniae, Haemophilus influenzae, Chlamydia pneumonia