Answer:
D). Correct the sentence fragments.
Step-by-step explanation:
Fluency is one of the crucial elements to deliver the intended idea or thought effectively to the readers.
As per the question, the best way to improve the fluency of the paragraph's sentence would be 'correcting/rectifying the sentence fragments(lacking either a subject, action, etc.)' as these fragments break the flow of the sentence and idea as well that affects the efficacy of the thought and prevents accomplishing its meaning. Thus, the rectification of the fragments would complete the thought and offer a comprehensive meaning to the sentence and the passage. Thus, option D is the correct answer.