What is the correct order of medication administration from fastest to slowest?

The correct order of medication administration from fastest to slowest is based on how quickly the medication enters the bloodstream and its onset of action.

Inhalation delivers medication directly to the lungs, which provides a rapid onset of action because the medication is absorbed quickly into the bloodstream through the alveoli. This is typically the fastest route of administration.

Sublingual administration involves placing medication under the tongue, where it dissolves and is absorbed directly into the blood vessels in the oral mucosa, leading to a quicker effect than oral medications that must pass through the digestive system first.

Suppository administration allows for medication absorption through the rectal mucosa. While it is generally quicker than oral medications, the onset of action can vary and is typically slower than both inhalation and sublingual routes.

Oral administration involves swallowing medicine, which then goes through the gastrointestinal tract before being absorbed into the bloodstream. This route usually has the slowest onset of action due to the time required for digestion and absorption.

Thus, the order of administration based on speed is: inhalation (fastest), sublingual, suppository, and finally, oral (slowest). This reasoning supports the choice of C as the correct answer.