The correct answer is B. The temperature dropped on the first day of fall, bringing welcomed relief. Everyone was happy wearing their new sweaters.
Explanation:
In language, sentence fluency refers to the way words flow together, this implies ideas and words have a natural rhythm and imitate oral language. In these terms, each idea is expressed using a sentence, rather than including multiple choppy or short sentences. Besides this, fluency implies using punctuation marks when necessary as wells as transitions.
According to this, the best example of sentence fluency is "The temperature dropped on the first day of fall, bringing welcomed relief. Everyone was happy wearing their new sweaters" because this sentence avoids dividing ideas into multiple choppy sentences, and instead integrates the information in two main sentences using punctuation marks only when necessary.