This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urology, Subject name: Surgery
Commonest cause of acute folliculitis (hair follicle infection) is 
Select and explain. 
A. Staphylococcus aureus, B. Beta hemolytic streptococcus, C. Propionibacterium acnes, D. Streptococcus viridans
A: Staphylococcus aureus
Answer: A: Staphylococcus aureus 
Explanation: Acute folliculitis are of two types: superficial and deep. The most common causative organism is Staphylococcus aureus. Superficial folliculitis is also caused by Pseudomonas aeruginosa.Reference : page 41 IADVL's Concise Textbook of Dermatology