Name the cranial nerves primarily responsible for eye movements and their general roles.

• A. CN III – most extraocular muscles and pupil constriction; CN IV – superior oblique; CN VI – lateral rectus
• B. CN II – image formation; CN III – pupil dilation; CN V – facial expression
• C. CN I – olfaction; CN II – optic; CN III – levator palpebrae
• D. CN VII – facial; CN IX – glossopharyngeal; CN X – vagus

Answer: (A)

Eye movement is controlled by three cranial nerves that innervate the extraocular muscles. The oculomotor nerve supplies most of these muscles (medial rectus, superior rectus, inferior rectus, and inferior oblique) and also carries parasympathetic fibers to constrict the pupil. The trochlear nerve governs the superior oblique muscle, which helps rotate the eye downward and inward. The abducens nerve controls the lateral rectus, which moves the eye outward.

So the best choice lists these three nerves with their respective roles: the oculomotor nerve for most eye muscles and pupil constriction, the trochlear nerve for the superior oblique, and the abducens nerve for the lateral rectus. Other options mix in functions not related to eye movement—vision processing and facial or other autonomic functions—so they don’t fit the question about which nerves primarily move the eye.