Which of the following can cause premature ventricular contractions?

Premature ventricular contractions (PVCs) are extra heartbeats originating in the ventricles, and they can be triggered by several factors. Electrolyte imbalances, such as low potassium or magnesium levels, significantly affect the electrical conduction system of the heart and can lead to PVCs. Similarly, drug use—including stimulants like caffeine, alcohol, and certain medications—can also irritate the heart and provoke these extra beats.

The other options do not typically contribute to the occurrence of PVCs. Increased cardiac output and adequate hydration generally support heart function and stability rather than induce arrhythmias. Stable angina and regular exercise typically signify that the heart is responding well to stress, while controllable hypertension and diet can usually be managed to reduce cardiovascular risks rather than acting as direct causes for PVCs.