Answer:
The main reason that this novel is a coming of age story is 1)
Step-by-step explanation:
As this novel is made for young people, that is one factor that this is made as a coming of age story. Since the main character is young, coming to understand himself, and that the process is happening over a number of years, the factors are hinting to a coming of age story. But the most important factor is that he is a young person and he is starting to understand himself. So therefore the correct answer is 1).