The correct answer is C. The "lie" is that a citation engine is a good replacement for knowing how to cite properly.
In reality, citation engines are often flawed and provide incomplete citations. While a citation engine is a good start, the student must check a citation engine's suggested citation to ensure it is correct. Often a citation engine's citation needs to be corrected or material needs to be added.
Furthermore, citation guidelines are often updated, so a citation engine may be outdated. Also, teachers might specify their own citation requirements. For these reasons, a citation engine may not be a trustworthy way to generate a citation.
Ultimately, a student needs to know how to cite his or her sources.