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
[{'content': 'What is the most common cause of pyogenic liver abscess \nSelect and explain. \nA. Trauma, B. Biliary tract infection, C. Colonic Diveiculitis, D. Appendicitis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: 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', 'role': 'assistant'}]