The proper question for Nina to ask in evaluating the source's credibility as she studies communist propaganda is <u>D. What is the </u><u>author's purpose</u><u> in creating this source</u>?
<h3>What factors inform a source's credibility?</h3>
The factors that inform a source's credibility include depth, objectivity, currency, authority, and purpose.
Here, the purpose refers to the author's purpose in creating the source.
Nina should not be concerned with the length of reviewing the source, whether the source is a book or documentary, or the language of the source.
Thus, Nina's concern in evaluating the source's credibility is <u>D. the</u><u> author's purpose</u>.
Learn more about a source's credibility at brainly.com/question/8061265
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