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: Medicine
The drug of choice in patients with Wolff-Parkinson-White syndrome with atrial fibrillation is 
Select and explain. 
A. Digitalis, B. Procainamide, C. Verapamil, D. Adenosine
B: Procainamide
Answer: B: Procainamide 
Explanation: None