The correct answer is B. Ventricular tachycardia only.

There are two primary shockable rhythms in cardiac arrest:

Ventricular fibrillation (VF)

Ventricular tachycardia (VT)

However, only one of these may still produce a pulse under certain conditions.

Why B is correct:

Ventricular tachycardia (VT) can occur with or without a pulse.

In some cases, VT allows the heart to generate enough cardiac output to produce a palpable pulse (this is called stable or unstable VT with a pulse).

Therefore, VT is the only shockable rhythm that may still have a pulse.

Why the other options are incorrect:

A. Ventricular fibrillation only → VF produces no organized cardiac activity, therefore no pulse

C. Both shockable rhythms → Incorrect because VF never produces a pulse

D. Neither a shockable rhythm → Incorrect because VT can produce a pulse

Exact Extracts:

“Ventricular fibrillation results in no effective cardiac output and no pulse.”

“Ventricular tachycardia may be present with or without a pulse.”

“Pulseless ventricular tachycardia and ventricular fibrillation are treated with defibrillation.”