What motor functions are performed by the Oculomotor nerve besides eye movement?

The Oculomotor nerve primarily functions in controlling most of the eye's movements, but it also plays a crucial role in the autonomic regulation of pupil size. Beyond facilitating eye movements, the nerve is responsible for pupil constriction, which is a vital function for regulating the amount of light entering the eye and assisting in focusing on near objects. This constriction is achieved through the parasympathetic fibers that the Oculomotor nerve carries, innervating the sphincter pupillae muscle in the iris.

The other options relate to functions that are not associated with the Oculomotor nerve. Facial movement is primarily controlled by the Facial nerve, hearing is the responsibility of the Vestibulocochlear nerve, and taste sensations are mediated by the Facial nerve for the anterior two-thirds of the tongue and the Glossopharyngeal nerve for the posterior one-third. Thus, the unique contribution of the Oculomotor nerve in mediating pupil constriction distinguishes it within the realm of cranial nerve functions.