Abducens supplies
**Core Concept**
The abducens nerve, the sixth cranial nerve, is responsible for innervating the lateral rectus muscle, which is one of the extraocular muscles responsible for eye movement. The abducens nerve plays a crucial role in controlling lateral gaze and maintaining binocular vision.
**Why the Correct Answer is Right**
The lateral rectus muscle is responsible for abducting the eyeball, moving it away from the midline of the body. The abducens nerve, specifically the oculomotor nerve nucleus in the pons, regulates the contraction and relaxation of the lateral rectus muscle through the release of neurotransmitters. The abducens nerve also receives input from the vestibular system to coordinate eye movements with head movements.
**Why Each Wrong Option is Incorrect**
**Option A:** This is a distractor and is not a correct answer.
**Option B:** This is a distractor and is not a correct answer.
**Option C:** This is a distractor and is not a correct answer.
**Clinical Pearl / High-Yield Fact**
The abducens nerve is unique in that it is the only cranial nerve that has a long intracranial course, making it susceptible to damage from increased intracranial pressure or lesions in the brainstem.
**Correct Answer:** D. Lateral rectus muscle.