Linda keeps her desk piled high with books and a. messy with papers b. with papers all around c. papers falling everywhere d. papers

Hi! The answer would be option D, papers.

Explanation:

The sentence is telling us that linda has a desk with piles of books and something else. Option D here is what makes the most sense cause "papers" would add to the list of things Linda has in her desk.

Option A and D could fit but we can assume that if Linda has her desk piled with things, her desk is messy, so it'd be redundant. Option B doesn't fit quite well because of the word "with" since theres another connctor already in place ("and").  

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