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: Pharmacology
[{'content': 'Drug useful in hepatic encephalopathy is: \nSelect and explain. \nA. Magnesium sulphate, B. Lactulose, C. Bisacodyl, D. Biphosphonates', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (B) Lactulose(Ref: KDT 8th/e p725)Lactulose is a laxative that acts by conversion to short chain fatty acids in the colon.These fatty acids result in decrease in pH of intestinal juice.At low pH, ammonia becomes ionized (NH4+ ) and thus cannot be absorbed.', 'role': 'assistant'}]