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
A synchronous cardioversion is given in 
Select and explain. 
A. AF, B. Ventricular fibrillation, C. Atrial flutter, D. Ventricular tachycardia
B: Ventricular fibrillation
Answer: B: Ventricular fibrillation 
Explanation: None