This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: A.N.S., Subject name: Pharmacology
[{'content': "Which of the following beta blocker doesn't cause bradycardia? \nSelect and explain. \nA. Pindolol, B. Labetalol, C. Bisoprolol, D. Atenolol", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. PindololPindolol is beta blocker with intrinsic sympathomimetic activity. These drugs themselves activate beta 1/2 sub maximally.', 'role': 'assistant'}]