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: Medicine
[{'content': 'Which of the following is the treatment of choice for Atrial fibrillation in patients with WPW syndrome who are hemodynamically unstable \nSelect and explain. \nA. Procainamide, B. Digoxin, C. DC Cardioversion, D. Radio-frequency ablation of the bypass tract', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Administration of AV nodal-blocking agents including oral or intravenous verapamil, diltiazem, beta block- ers, intravenous adenosine, and intravenous amiodarone are contra- indicated. Preexcited tachycardias should be treated with electrical cardioversion or intravenous procainamide or ibutilide, which may terminate or slow the ventricular rate. Ref Harrison 20th edition pg 1532', 'role': 'assistant'}]