Which combining form refers to the 'nose'?

The combining form that refers to the 'nose' is rhin/o. This term is derived from the Greek word 'rhis,' which translates to 'nose.' In medical terminology, this combining form is often used in various terms related to the nose and nasal cavities, such as rhinitis (inflammation of the nasal passages) and rhinoplasty (surgical repair of the nose). Understanding this combining form is essential in the context of otolaryngology, the branch of medicine that focuses on the ears, nose, and throat.

In contrast, the other options refer to different anatomical structures: ren/o pertains to the kidneys, rhytid/o involves wrinkles, and rect/o refers to the rectum. Each of these has its specific use in medical terminology, but they do not relate to the nose itself, making rhin/o the correct choice for this question.