What nerve is NOT involved in innervating the extraocular muscles?

The correct choice highlights that the trigeminal nerve (CN V) is not primarily involved in the innervation of the extraocular muscles. The extraocular muscles, responsible for controlling eye movement, are primarily innervated by cranial nerves III, IV, and VI.

Cranial nerve III (oculomotor nerve) innervates most of the extraocular muscles, allowing for movements such as adduction and downward gaze. Cranial nerve IV (trochlear nerve) innervates the superior oblique muscle, which helps to rotate the eyeball. Cranial nerve VI (abducens nerve) is responsible for innervating the lateral rectus muscle, allowing for abduction of the eye.

In contrast, cranial nerve V (trigeminal nerve) is predominantly responsible for sensory innervation to the face and muscles of mastication, not for the motor control of extraocular movements. This distinction underscores why option B is the correct answer, as it does not play a direct role in the motor function of the extraocular muscles.