really really need help!!

Gatsby of course. Go back to the second page of the novel wherein we try to figure out what has Nick wanting everyone to be at a "uniform attention". He says that Gatsby is the only one "exempt from his unaffected scorn." He also goes on to mention that that there was something "gorgeous" about the guy with his "heighten sensitivity" and "romantic readiness". It also says it was "Gatsby that turned out all right in the end" and further elaborates that it was what "preyed on Gatsby" that made Nick disgusted with a particular class of American society.

Based on the flashback method of telling the story, we know that the upper, elite class of Tom and Daisy, who "hide behind their money," is what enhances Nick's loathing of the American aristocracy, something Gatsby could only dream of.