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
In which of the following types of cardiac arrest is DC counter shock the only definitive treatment? 
Select and explain. 
A. Asystole, B. Electromechanical dissociation, C. Ventricular fibrillation, D. All of the above
C: Ventricular fibrillation
Answer: C: Ventricular fibrillation 
Explanation: None