Sentence Correction (SC) | Re: One of the earliest known birds with a beak and contour feathers, Conf

Pay attention to the different pronouns in the answer choices. We can choose "on its wings" or "on their wings." The pronoun's antecedent is 'Confuciusornis sanctus,' which is singular, so we want "on its wings." Eliminate B and E. Next, we have another pronoun split "helped them" or "helped it." The pronoun is still referring to Confuciusornis sanctus, so again, we want "it." Eliminate A and C. All that's left is D, which is the answer.
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