## Core Concept
Drowning is a form of asphyxia due to aspiration of liquid entering the airway, which can lead to cardiac arrest. The mechanism of cardiac arrest in drowning involves hypoxia and hypercapnia.

## Why the Correct Answer is Right
The correct sequence of events leading to cardiac arrest in drowning typically involves an initial period of hypoxia due to the aspiration of water, which can cause laryngospasm. This leads to asphyxia, and if the victim does not manage to breathe, it progresses to a hypoxic cardiac arrest. The typical arrest rhythm in drowning is often **asystolic** or **pulseless electrical activity (PEA)**, rather than ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) seen in other cardiac arrests.

## Why Each Wrong Option is Incorrect
**Option A:** VF is more commonly associated with cardiac arrests due to myocardial infarction or other heart conditions, not typically drowning.
**Option B:** VT is also more commonly associated with cardiac conditions and not the typical arrest rhythm in drowning.
**Option D:** While PEA can be a feature, stating it as the typical arrest might not fully capture the initial presentation as effectively as asystole.

## Clinical Pearl / High-Yield Fact
In cases of drowning, early CPR and rescue breathing are critical. The American Heart Association emphasizes that **drowning victims often have a significant hypoxic component** to their arrest, making early and effective ventilation crucial.

## Correct Answer Line
**Correct Answer: C. Asystole.**