B is the correct answer. The other answers are either adjectives - nouns.
The correct answer for the question that is being presented above is this one: "D. Verb." The newest study invalidates parts of the conclusions made in earlier studies. The <span>part of speech is that invalidates is verb.</span>
Here are the following <span>choices:
A. Adjective
B. Adverb
C. Noun
D. Verb </span>
