Final answer:
The sentence 'The strange new guests filled the dance floor' is already in active voice, as the subject is doing the action. The correct answer to the given question is D) No change. The sentence is already active.
Step-by-step explanation:
To change a sentence from a passive voice to an active voice, the subject must be the doer of the action instead of being acted upon. The sentence in question, "The strange new guests filled the dance floor," is already in the active voice because the subject, 'the strange new guests,' are performing the action of 'filling' the dance floor. Therefore, the answer is: D) No change. The sentence is already active.
It might help to know how to identify passive voice. You'll see a form of the be verb (am, is, are, was, were), followed by the past participle of the verb, often with the preposition 'by.' For example, 'The dance floor was filled by the strange new guests' is in passive voice. However, the original sentence does not use this construction and is in the active voice, as the guests are actively doing the filling of the dance floor.