This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Pharmacology
Which of the following medications would be prescribed most freequently to patients suffering from chronic atrial fibrillation? 
Select and explain. 
A. Lidocaine, B. Bretylium, C. Warfarin, D. Adenosine
C: Warfarin
Answer: C: Warfarin 
Explanation: (Ref: KDT 6/e p604) Patients of chronic atrial fibrillation are at high risk of developing thromboembolism. Oral anticoagulants are most frequently advised drugs in these patients to decrease the risk of this adverse effect.