What is the action of a plagiarist?

The action of a plagiarist involves presenting someone else's work as their own. This dishonest practice can take many forms, including copying text from books, articles, or websites without proper citation, or paraphrasing someone else’s ideas without acknowledgment. Plagiarism undermines the integrity of academic and creative work by misrepresenting the author’s original source, leading to a lack of trust and credibility in the work presented.

In the context of the other choices, creating original content is the opposite of plagiarism, as it involves generating new ideas or works. Reviewing someone else's ideas can be a legitimate academic activity, especially when properly credited, and does not imply any intent to claim those ideas as one's own. Collaborating on a project entails shared contributions and ideas among individuals and should also involve transparency in the attribution of ideas. None of these alternatives capture the essence of what plagiarism entails, which is why presenting someone else's work as one's own is the correct identification of a plagiarist's action.