Which nerve provides motor innervation to the intrinsic muscles of the tongue?

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Motor control for shaping the tongue comes from the hypoglossal nerve. It is the sole source of motor innervation to the intrinsic tongue muscles—the ones that change the tongue’s shape, such as the superior and inferior longitudinal, transverse, and vertical muscles. The hypoglossal nerve also supplies most of the extrinsic tongue muscles, except for palatoglossus, which gets innervation from the vagus nerve. The other nerves listed are primarily sensory: the lingual nerve (a branch of V3) carries general sensation and, via a hitchhiking path with chorda tympani, taste from the anterior two-thirds; glossopharyngeal nerve handles sensation and taste for the posterior one-third; and vagus contributes to innervation of the palatoglossus. So for motor innervation of the intrinsic tongue muscles, the correct nerve is the hypoglossal nerve.