Which assessment provides information about the function of cranial nerve III?

The assessment that provides information about the function of cranial nerve III (the oculomotor nerve) involves instructing the client to look up and down without moving their head. Cranial nerve III is primarily responsible for eye movement, specifically controlling several muscles that enable the eye to move in multiple directions. This includes movements up, down, and inward.

By asking the client to look up and down, you are directly evaluating the ability of the eyes to respond appropriately to the commands, which reflects the integrity of cranial nerve III. Healthy function of this nerve ensures that the eye movements are smooth and coordinated, without any restriction or deviation.

The other options each correspond to assessments related to different cranial nerves or general motor skills, which do not specifically target the functionality of cranial nerve III. Therefore, the action of looking up and down directly assesses the relevant cranial nerve, making it the correct choice.