**Core Concept**
Mitral valve prolapse (MVP) is a condition characterized by the bulging of the mitral valve leaflets into the left atrium during systole, often due to myxomatous degeneration of the valve. The increased stress on the mitral valve can lead to various arrhythmias.

**Why the Correct Answer is Right**
The most common arrhythmia associated with MVP is supraventricular tachycardia (SVT), particularly paroxysmal supraventricular tachycardia (PSVT). This is thought to be due to the abnormal electrical activity generated by the mitral valve leaflets, which can act as a focus for ectopic beats. The increased frequency of ectopic beats can lead to re-entry circuits, resulting in SVT. The atrioventricular (AV) node plays a crucial role in the initiation and maintenance of SVT in MVP patients.

**Why Each Wrong Option is Incorrect**
**Option A:** Atrial fibrillation is not the most common arrhythmia in MVP. While atrial fibrillation can occur in MVP, it is more commonly associated with other conditions such as hypertension, coronary artery disease, and heart failure.
**Option B:** Ventricular tachycardia is a less common arrhythmia in MVP and is often associated with more severe structural heart disease.
**Option C:** Sinus bradycardia is not typically associated with MVP, as the condition is more commonly linked to supraventricular tachycardias.

**Clinical Pearl / High-Yield Fact**
MVP patients with SVT may exhibit symptoms such as palpitations, lightheadedness, and shortness of breath. The arrhythmia can be terminated with vagal maneuvers, such as the Valsalva maneuver or carotid massage.

**Correct Answer:** C. Supraventricular tachycardia (SVT).