That is called a Thesaurus. It lists synonyms and antonyms.
A gpa is a number that is based off your grades
Since <em>ostentatious </em>and <em>modest </em>are antonyms, their meanings are completely opposite, we need to find a pair of words which also denote something different. The correct answer is reticent:talkative, because reticent is shy, and talkative is obviously not.
