Which of the Following Is a Legal and Ethical Practice

Which of the following is a legal and ethical practice?

A) Copying someone else's written work found on the Internet and presenting it as your own, as long as it is for schoolwork.
B) Trying shareware for free and paying for it only after you decide to keep using it.
C) Downloading copyrighted artwork and using it as a background on your Web site.
D) Downloading music and motion pictures as long as they are from a peer-to-peer network.