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
"Epiglottitis" is mainly caused by: 
Select and explain. 
A. Streptococcus, B. Staphylococcus, C. Haemophilus, D. Mycoplasma
C: Haemophilus
Answer: C: Haemophilus 
Explanation: Haemophilus