This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Pharmacology
[{'content': 'All of the following drugs are used as oral treatment for arrhythmia except: \nSelect and explain. \nA. Amiodarone, B. Esmolol, C. Quinidine, D. Verapamil', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. EsmololEsmolol is shortest acting beta blocker, it has to giveni/v for acute therapy. Rest of the drugs can be given via oral route.', 'role': 'assistant'}]