The correct answer is C. Dictionary of synonyms
Explanation:
A thesaurus is a type of source or document that includes the words of a language along with the synonyms or words that belong to the same field. This means, different to a regular dictionary thesaurus do not include the meaning of words but the words that the synonyms of a word and in some cases the antonyms of it. Additionally, one of the most famous thesaurus in the English language is Roget's Thesaurus which was a thesaurus written by a British Lexiocrapher Peter Mark Roget that classifies words according to their similarities in meaning or synonyms and that was written by the author to help people in the task of writing. Therefore it is true Roget's Thesaurus is a dictionary of synonyms.
