This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Longest acting thiazide diuretic is: \nSelect and explain. \nA. Chlorthiazide, B. Chlorthalidone, C. Indapamide, D. Metolazone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Chlorthiazide : Shortest acting\nChlorthalidone : Longest acting', 'role': 'assistant'}]