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: ENT
Commonest causative organism for acute tonsillitis is which of the following? 
Select and explain. 
A. B streptococci, B. Parainfluenza virus, C. H influenza, D. Corynebacterium
A: B streptococci
Answer: A: B streptococci 
Explanation: Parainfluenza virus causes tracheobronchitis and H influenza cause acute epiglottitis.