OEIf you chose (A), the word second verb “adding” is not parallel with the initial verb “chose.” We’re looking for another simple past tense verb to make the sentence correct.
If you chose (B), “adding” is not parallel with the earlier verb “chose” and the phrase “as well as” is wordy. In order to use the idiom “as well as” in this context, we would need to omit the verb “adding.”
If you chose (C), the conjunction “and” and the word “additionally” are redundant. That is, the meaning of one is inherently contained in the other. Look for a more concise choice.
(D) is the correct response. The conjunction “yet” provides the correct meaning by contrasting with the phrase “mostly” in the first-half of the sentence. More importantly, “added” is parallel with “chose.”
If you chose (E), we’d need an article in front of “addition” for this sentence to be grammatically correct, but more importantly changing the verb to a noun doesn’t allow the two halves of the sentence to be parallel.
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