We're asked to justify the application of a principle. The principle is a conditional relationship:
If a professor is to make the determination that someone committed plagiarism, then the professor should believe that the student knowingly presented someone else's ideas as if they were their own.
DP --> PB
(Notation Key: DP - determine to be plagiarism, PB - professor believes student presented someone else's ideas without attribution)
The application of the principle relies on the contrapositive. So if the professor does not believe the student presented someone else's ideas, then the professor should not make the determination that the student plagiarized. In order for the application to be justified, we need an answer choice that states that the professor does not believe the student presented someone else's ideas without attribution.
Correct Answer
Answer choice (C) states that the professor does not believe the student presented someone else's ideas without attribution.
Incorrect Answers
(A) may be tempting, but is not strong enough. Not having compelling evidence is not the same as not believing. Professor Serfin may believe that Walters presented someone else's ideas, but is not able to prove it!
(B) is out of scope. We care about what the professor believes.
(D) is out of scope. We do not care about what Walter believes, but rather what professor Serfin believes.
(E) would not justify the application of the principle. What professor Serfin plans to do, does not justify what professor Serfin should do.