Answer: All the above
Explanation:
Plagiarism is to steal and pass off (the ideas or words of another) as one's own to use (another's production) without crediting the source, to commit literary theft to present as new and original, an idea or product derived from an existing source.
Other acts of plagiarism are, turning in someone else's work as your own, copying words or ideas from someone else without giving credit, failing to put a quotation in quotation marks, giving incorrect information about the source of a quotation, changing words but copying the sentence structure of a source without giving credit, copying so many words or ideas from a source that it makes up the majority of your work whether you give credit or not.
Most cases of plagiarism can be avoided, however, by citing sources. Simply acknowledging that certain material has been borrowed and providing your audience with the information necessary to find that source is usually enough to prevent plagiarism.
In other words, plagiarism is an act of fraud. It involves both stealing someone else's work and lying about it afterward.