question: Q:A 50-year-old man with a history of atrial fibrillation presents to his cardiologist’s office for a follow-up visit. He recently started treatment with an anti-arrhythmic drug to prevent future recurrences and reports that he has been feeling well and has no complaints. The physical examination shows that the arrhythmia appears to have resolved; however, there is now mild bradycardia. In addition, the electrocardiogram recording shows a slight prolongation of the PR and QT intervals. Which of the following drugs was most likely used to treat this patient?? 
  {'A': 'Carvedilol', 'B': 'Metoprolol', 'C': 'Propranolol', 'D': 'Sotalol', 'E': 'Verapamil'},