Answer:
D. The excerpt should be revised because it contains a dependent clause that leaves the writer’s thought unfinished.
Step-by-step explanation:
The given excerpt needs revision because it is incomplete sentence. The sentence begins with 'because' which represents 'sentence fragments.' Sentence fragments is that incomplete sentence which is disconnected from it's main clause.
The excerpt needs an independent clause to present the complete and finished thoughts of the writer. It is a dependent clause and therefore, does not gives author's finished thoughts. Therefore, option D is correct.