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
An elderly male patient presented with fever, chest pain, and dry coughp; sputum culture showed growth on Charcoal Yeast Extract Medium, the organism is 
Select and explain. 
A. H. influenza, B. Moraxella catarrhalis, C. Legionella, D. Burkholderia cepacia
C: Legionella
Answer: C: Legionella 
Explanation: None