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
[{'content': 'All are common causes of a pyogenic liver abscess Except \nSelect and explain. \nA. E. coli, B. Proteus, C. Klebsiella, D. Staphylococcus', 'role': 'user'}, {'content': 'Answer: B \nExplanation: E. coli- MC in western countriesKlebsiella pneumonia- MC in Asian countriesStaphylococcus- MC in children, suffering from a chronic granulomatous disease', 'role': 'assistant'}]