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 intra peritoneal abscess? 
Select and explain. 
A. Morrison's pouch, B. Omental bursa, C. Pelvic region, D. Left subhepatic pouch
C: Pelvic region
Answer: C: Pelvic region 
Explanation: Pelvic abscess is the most common intraoeritoneal abscess(50-60%).Causes include- appendicitis,pelvic infections,sequelae of diffuse peritonitis,post operative and other abdominal causes.Organisms include Bacteroides fragilis,E.coli,anaerobic streptococci. Reference :SRB's manual of surgery,5th edition,page no:574.