Drooling is the participle in this sentence.
Answer:
Ralph says, in chapter 9, that the boys are going to Jack's tribe so they can have fun and act like children. He says the boys are leaving him so they can hunt, pretend to be a tribe, and put on war paint. Jack offers the boys excitement and lures them with food from his hunts.
B. They are spies for the Nazis, and Anne suspects this.
The t-shirt that they give only to people who finish is a big reason that so many people take up the challenging race.
This paraphrase presents the same information as in the sentence, but since it should be a bit more of a summary, it takes out the specific detail of how many people actually run the race, which can just be paraphrased into 'so many'.