The correct answer is a thesaurus
Step-by-step explanation:
A thesaurus is a dictionary that lists words that have a similar meaning (synonyms) or that are somehow related, also, Thesaurus include words that have an opposite meaning (antonyms). Thesaurus can be found as books, online web pages or software which make thesaurus quite accessible and easy to use. The purpose of using a thesaurus is to find similar or opposite words and thus, a thesaurus is useful to avoid repetition. Because of this Jon can use a Thesaurus as a tool to avoid redundancy when writing a research paper.