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
The commonest organism causing cellulitis is ? 
Select and explain. 
A. Streptococcus pyogenes, B. Streptococcus faecalis, C. Streptococcus viridans., D. Microaerophilic streptococci
A: Streptococcus pyogenes
Answer: A: Streptococcus pyogenes 
Explanation: Ans. is 'a' i.e., Streptococcus pyogenes