**Core Concept**
Acute aseptic meningitis in children is most commonly caused by viral infections, with enteroviruses being the predominant pathogen due to their widespread circulation and ability to invade the central nervous system.

**Why the Correct Answer is Right**
Enteroviruses, such as coxsackieviruses and echoviruses, are the leading cause of aseptic meningitis in children worldwide. They infect the meninges and cause inflammation through direct viral invasion and immune-mediated responses. These viruses are highly contagious, commonly spread via the fecal-oral route and respiratory droplets, and are frequently detected in children with meningitis, especially during summer and early fall. Their prevalence in pediatric populations makes them the most frequent etiology.

**Why Each Wrong Option is Incorrect**
Option A: Arboviruses (e.g., West Nile) are rare causes of meningitis in children and are more common in endemic areas.
Option B: Respiratory syncytial virus (RSV) primarily causes lower respiratory tract infections and is not a significant cause of meningitis.
Option D: Herpesviruses (e.g., HSV) can cause meningitis but are typically associated with immunocompromised patients or neonatal infections, not the most common cause in healthy children.

**Clinical Pearl / High-Yield Fact**
Enteroviruses are the most common cause of aseptic meningitis in children—especially in those under 5 years—and are often associated with mild to moderate fever, headache, and photophobia. A lumbar puncture may show elevated white blood cells and normal glucose, with a low probability of bacterial infection.

✓ Correct Answer: C. Enterovirus