A nurse is reinforcing teaching with a group of nurses about medication administration. Which of the following routes of administration provides the most rapid onset for the client?

A. Intravenous: IV administration delivers medication directly into the bloodstream, allowing for the fastest onset of action (within seconds to minutes). B. Topical patch: Slow absorption, designed for long-term, sustained release. C. Sublingual: Faster than oral, but slower than IV (absorbed through mucous membranes). D. Intramuscular: Faster than oral, but slower than IV, as the drug must diffuse into the bloodstream from muscle tissue.