Answer:
The complete subject in the sentence above is the following one: Many of the candidates (D)
Explanation:
The subject of the sentence is the person, thing, place, or idea that is performing the action depicted by the verb. In order to identify the subject, you should ask the following question: Who verb/ed? and the answer to that question is the subject of the sentence. For instance who spoke at the forum last night? Answer: Many of the candidates. The NP "many of the candidates" is the subject of the sentence.