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: Anatomy
What is the most common cause of pyogenic liver abscess 
Select and explain. 
A. Trauma, B. Biliary tract infection, C. Colonic Diveiculitis, D. Appendicitis
B: Biliary tract infection
Answer: B: Biliary tract infection 
Explanation: Routes of infection Biliary tract (Most Common) - CBD stones leading to cholangitis, Hilar carcinoma in Western countries, CBD strictures Poal vein (2nd most common) Hepatic aery - Hematogenous spread, usually monimicrobial, Staphylococcus or streptococcus Direct extension- from subdiapragmatic abscess, from suppurative cholecystitis, from empyema in chest, from perinephric abscess Penetrating or blunt trauma Cryptogenic Ref: Sabiston 20th edition