Gatsby does not actually offer Nick a job, but suggests that he could help him out financially through his vast network of business connections. Nick resents and declines this offer of assistance because he knows Gatsby is only offering to reward him for enabling him to meet with Daisy and for them to use Nick’s little cottage as a place for further meetings
"A.to help foster peace and economic collaboration among Europeans nations" is the correct answer. It was one of the solutions to ending violence after World War II.
