## Core Concept
The oculomotor nerve, also known as the third cranial nerve (CN III), is primarily responsible for controlling the movements of the eye through innervation of the extraocular muscles. It supplies most of the extraocular muscles but not all.

## Why the Correct Answer is Right
The oculomotor nerve (CN III) supplies the following extraocular muscles:
- **Medial rectus**: involved in adduction of the eyeball.
- **Superior rectus**: involved in elevation and adduction.
- **Inferior rectus**: involved in depression and adduction.
- **Inferior oblique**: involved in extorsion, elevation, and abduction.
- **Levator palpebrae superioris**: involved in eyelid elevation.

However, CN III does not supply the **Lateral rectus** muscle, which is responsible for abduction of the eyeball. The lateral rectus muscle is actually innervated by the **Abducens nerve (CN VI)**.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is not provided, but based on the context, we can infer that it would be incorrect because it does not accurately represent the muscle not supplied by CN III.
- **Option B:** Similarly, without the specific content of Option B, we assume it's incorrect for not accurately identifying the exception.
- **Option C:** This option is also not provided but would be incorrect if it does not correctly identify the lateral rectus as the exception.

## Clinical Pearl / High-Yield Fact
A key clinical correlation to remember is that a **third nerve palsy (oculomotor nerve palsy)** results in ptosis (drooping eyelid), a dilated pupil (if the parasympathetic fibers are affected), and an inability to move the eye in certain directions (specifically, adduction, elevation, depression, and intorsion). The eye may appear "down and out" due to the unopposed action of the unaffected muscles (lateral rectus and superior oblique).

## Correct Answer: D. Lateral rectus.