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': 'A patient on lithium therapy was found to be hypertensive also. Which of the following antihypertensive drugs is contraindicated in a patient on lithium therapy in order to prevent toxicity ? \nSelect and explain. \nA. Clonidine, B. Beta blockers, C. Calcium channel blockers, D. Diuretics', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]