This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
Drug used for atrial fibrillation and atrial flutter is 
Select and explain. 
A. Verapamil, B. Digitalis, C. Quinidine, D. Diphenylhydantoin
B: Digitalis
Answer: B: Digitalis 
Explanation: For AF, digoxin can be used- it decreases ventricular rate in AF Verapamil decreases conduction velocity and increases the refractory period of the AV node and so used in PSVT. REF.Essentials of Pharmacology KD Tripathi 8th ed.