This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
Most common site of anorectal abscess is? 
Select and explain. 
A. Perianal, B. Ischiorectal, C. Pelvirectal, D. Intersphincetric
A: Perianal
Answer: A: Perianal 
Explanation: Anorectal abscess: # Usually produces a painful, throbbing swelling in the anal region. The patient often has swinging pyrexia # Subdivided according to anatomical site into perianal, ischiorectal, submucous and pelvirectal # Underlying conditions include fistula-in-ano (most common), Crohn's disesase, diabetes, immunosuppression # Treatment is drainage of pus in first instance, together with appropriate antibiotics # Always look for a potential underlying problem Ref: Bailey & Love&;s Sho Practice of Surgery,E25,Page-1262