Vaunted means highly praised or much boasted about
English like any language has its own semantics, word arrangement (lexicon and structure) which cannot be abridged. Based on this, Vaunted is the word that best fits the context of the sentence. It implies that up till the time the team lost the last three games in a row, the team boasted an impressive record
<u>Hence, Option D (Vaunted) is the correct answer</u>