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': 'Beta 1 antagoinst used in congestive cardiac failure? \nSelect and explain. \nA. Atenolol, B. Metoprolol, C. Salbutamol, D. Terbutaline', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Metoprolol o Beta blockers approved for use in CHF are Carvedilol (most commonly used), metoprolol and bisoprolol. o Other agents can also be used (see above explanation).", 'role': 'assistant'}]