**Question:** In mumps, the most common eye lesion is:

A. Orbital cellulitis
B. Optic neuritis
C. Orbital lymphadenopathy
D. Orbital abscess

**Core Concept:** Mumps is a viral infection primarily caused by the paramyxovirus, which primarily affects the salivary glands. However, it can also involve other organs like the testes, ovaries, and pancreas. Mumps can lead to various complications, including ocular manifestations.

**Why the Correct Answer is Right:** Orbital cellulitis (Option D) is the correct answer because it is the most common complication of mumps affecting the eye. Orbital cellulitis is an inflammation of the soft tissues surrounding the orbit, which can lead to severe ocular morbidity and even vision loss if untreated. The correct answer is not B (optic neuritis) as it refers to inflammation of the optic nerve, which is less common compared to orbital cellulitis in mumps.

**Why Each Wrong Option is Incorrect:**

A. Orbital lymphadenopathy (Option C) is the swelling of the lymph nodes in the neck, which is a common manifestation of mumps but not the most common ocular complication.

B. Optic neuritis (Option B) is an inflammation of the optic nerve, which is less common than orbital cellulitis in mumps.

**Clinical Pearl:** Mumps can cause various ocular complications, making a thorough examination of the eye crucial in suspected cases. Prompt diagnosis and treatment are essential to prevent severe ocular morbidity and vision loss.