I'm not sure how to understand this question...
But if the question is asking about what the cat did, and how you would explain it?
or if they meant to explain that sentence...
if they mean to explain the sentence itself, I would say the answer is
A
But is they meant to tell about the next chapter, I would ASSUME the answer to be
B
The answer is: [D]:
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They are often used to combine choppy sentences.
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Conjunctions are often used to combine choppy sentences.
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Note: The questions asks about CONJUNCTIONS —NOT about "contractions".
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Choice "A" is incorrect. They are not used to combine two or more LONG sentences. If sentences are already long, then do not need to be combined with a conjunction.
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Choice: "B" is incorrect. To the contrary, the use of conjunctions actually makes sentences longer.
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Choice "C" is incorrect. To the contrary, the use of conjunctions should be used (appropriately, of course) in essays. The use of "contractions" should not be used in essays or formal writing.
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Choice "D" is correct. They are often used to combine choppy sentences for better reading and engagement.
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