Answer: it adds a more realistic feeling to the book.
Gatsby speaks to what's the matter with the American Dream. The way does the character of Gatsby most satisfy the meaning of oddity is that he is generally quiet, yet he is apprehensive before he sees Daisy. I hope the answer will help you.
He's trying to explain what exactly motivated him, particularly in the second paragraph. It was none of the things that would motivate someone to commit murder. Gain of any kind was out of the question. Feelings were not the motive. Nothing the old man had motivated him.
It was just his eye. So he's in a battle with himself. (That's the first answer).
We are leading up to something and we need to have a background. This is not the climax or the resolution. It is not the falling action -- just the opposite. It is the build up towards the climax.
So the only thing it can be is the exposition which is the second answer.