The closest correct answer is 4. An exterior water faucet, located at the sill.

Actually, a sillcock is a type of hose bib (the kind of water faucets that are used outside or at the clothes washer hook-up). What makes a sillcock different is that the threads where it connects to the house are female, and it is flared at the back so that when it is screwed into place the flared part acts to cover the hole in the wall where the pipe comes through.

Sillcocks aren't used much anymore, because modern plumbing pipe is connected with solder and/or compression fittings rather than threaded connections. Although a sillcock is about the same price as a hose bib, it is slightly more difficult to install because of stricter tolerances. We hope you win the contest.