To assess cranial nerve XII (hypoglossal nerve), you would ask the patient to:

The hypoglossal nerve (cranial nerve XII) is primarily responsible for innervating the muscles of the tongue, which are important for movements such as speaking, swallowing, and manipulating food within the mouth. To assess the function of this nerve, asking the patient to wiggle their tongue from side to side effectively tests the motor control of the tongue muscles. This action allows you to observe any weaknesses or asymmetries that may indicate dysfunction of the hypoglossal nerve.

In contrast, the other choices focus on functions that are associated with different cranial nerves. Raising eyebrows evaluates the function of the facial nerve (cranial nerve VII), testing hearing acuity pertains to the vestibulocochlear nerve (cranial nerve VIII), and identifying sweet taste assesses the sensory function of the facial nerve (again, cranial nerve VII) related to taste sensation on the anterior two-thirds of the tongue. Each of these actions does not directly involve the role of the hypoglossal nerve, which is dedicated to tongue movement. Therefore, the assessment directly related to cranial nerve XII is to have the patient wiggle their tongue from side to side.