Answer is A (Amiodarone) Amiodarone is the preferred antiarrhythmic agent jiff resuscitation in a patient with cardiac arrest. Amiodarone is the preferred antiarrhythmic agent for resuscitation, In patients with VF/VT that does not respond to CPR, defibrillation, and vasopressor therapy. Amiodarone is the first-line antiarrhythmic agent given during cardiac arrest because it has been clinically demonstrated to improve the rate of ROSC (Return of Spontaneous Circulation) and hospital admission in adults with refractory VF/pulseless VT. Amiodarone should be considered when VF/VT is unresponsive to CPR, defibrillation, and vasopressor therapy. If Amiodarone is unavailable, Lidocaine may be considered, but in clinical studies Lidocaine has not been demonstrated to improve rates of ROSC and hospital admission compared with Amiodarone. Procainamide may be used for stable wide QRS Tachycardia but not for pulseless cardiac arrest and must be avoided in Torsades De Pointes. Magnesium sulphate should be considered only for Torsades de pointes associated with a long QT interval