The sentence is c because which wasnt needed
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Tone, as you may know, is the general attitude an author takes in the construction of a story, essay, poem, etc. that can be determined by the author's choice of words. When we look at the essay, "Murmurs," by K.C. Cole, we see slang/informality in the author's word choice in the following sentence from the essay: "Because there's scientific gold in them there sinusoidal
hills." Additionally, there are many analogies and similes the author uses in the explanation of concepts such as when the author writes "Like children going after cookies the patterns of sloshing particles left their sticky fingerprints all over the sky." As such, one way to describe the author's tone would be informal (almost playful/humorous) yet informative.

To prevent warping, thin, organic bonded wheels such as those used for cutting-off should be laid flat on a horizontal surface of steel or similar rigid material away from excessive heat and moisture.22 To minimise deterioration, wheels must be stored in a room which is dry and not subject to extreme temperatures.
A pronoun can substitute a noun or a noun phrase. Among the options above only C. him and D. They are pronouns: stories is a noun and many could be a pronoun if is was standing alone, but here it is a part of a noun phrase.
C. him is singular, so the right answer is D. They