Which cranial nerve is responsible for motor control of the tongue?

The hypoglossal nerve is the cranial nerve responsible for motor control of the tongue. It innervates the muscles that are primarily responsible for tongue movement, enabling actions such as speaking, swallowing, and manipulating food. Specifically, the hypoglossal nerve supplies motor function to all intrinsic muscles of the tongue as well as most of the extrinsic muscles, allowing for a range of movements essential for these functions.

In contrast, the other nerves listed have different functions. The glossopharyngeal nerve primarily innervates the stylopharyngeus muscle involved in swallowing and provides sensation to the posterior third of the tongue. The facial nerve is mainly responsible for the muscles of facial expression and has taste function in the anterior two-thirds of the tongue, but does not control motor movement of the tongue. The trigeminal nerve is primarily responsible for sensation in the face and motor functions such as mastication, but it does not play a role in the motor control of the tongue itself. Therefore, the hypoglossal nerve is clearly identified as the correct choice due to its specific role in tongue movement.