How does Philip answer question number four on his English exam?

In Avi's Nothing But the Truth, question number four on Philip's Winter Term English exam for Margaret Narwin's class is:

What is the significance of Jack London's choice in making Buck, the dog in The Call of the Wild, the focus of his novel? Is the dog meant to be symbolic? Explain your answer. Can people learn from this portrayal of a dog? Expand on these ideas. 

Rather than provide a serious answer to this question, Philip chooses to be glib and to let his poor attitude spoil his efforts. He replies:

The significance of Buck in Jack London's novel The Call of the Wild is that Buck is symbolic of a cat. You might think that cats have nothing to do with the book, but that is the point. Dogs are willing to sit around and have writers write about them, which, in my personal opinion, makes them dumb. I think cats are smart. Cats don't like cold. A book that takes up so much time about a dog is pretty dumb. The book itself is a dog. That is what people can learn from Jack London's novel The Call of the Wild.

Miss Narwin is troubled by Philip's persistent disrespect and his lack of thoughtful intention, commenting that he needs to be "more than lazy in [his] thinking." She writes on his exam that she knows that he has the potential to do good work, particularly since his previous work has been much better; she also warns him that he is in danger of failing the class and gives him a "C-" on the grade.
This grade puts Philip's position on the track team in jeopardy, but still Philip can't seem to take responsibility for his own poor work ethic. He lashes out and tells Coach Jamison that he is only doing poorly because Miss Narwin doesn't like him and is too "old-fashioned" and "boring." Coach Jamison is sympathetic but informs Philip that he won't even be allowed to try out for the team.