Darren had to submit a research paper as part of his final exam. The assignment needed weeks of careful study and experimentation. Darren, however, did not work on the paper until the day before the submission. As a result, he had no choice but to use another research article and present the article as his own. In this scenario, Darren is guilty of _________.a. libelb. defamationc. slanderd.d. plagiarism