Which route involves the insertion of a suppository into the body?

The correct answer is the rectal route. This method specifically involves the insertion of a suppository into the rectum, where it can dissolve and be absorbed into the bloodstream, providing local or systemic effects. It is commonly used for various medications, such as those for pain relief, nausea, or bowel movements, making it a valuable option for patients who may be unable to take medications orally due to vomiting, difficulty swallowing, or other issues.

In contrast, the otic route pertains to medications administered into the ear, the vaginal route involves medications placed into the vaginal canal, and the ophthalmic route refers to drugs applied to the eyes. These routes serve different purposes and target different areas of the body, highlighting the unique characteristics and applications of each method of administration.