The correct answer is D. A thesaurus
Step-by-step explanation:
In writing, it is common for novice writers to feel they cannot find an appropriate word or the synonym of another word, which is especially important to avoid the unnecessary repetition of terms or the use of words that are not adequate. In this case the most advisable is to use reference material, especially a thesaurus as this material lists the words of a language along with their synonyms or related word, which made it a suitable material for finding appropriate words related to a field or another word. On the other hand, a vertical file refers to a collection of booklets, photographs, and other materials; a gazetteer is a geographical dictionary used to understand maps and a facsimile is a copy of a document or book and therefore any of these materials or sources can be used to find an appropriate word while writing. Thus, to find an appropriate word while writing use a thesaurus.