Why does nick say this to gatsby: "you're worth the whole d*** bunch put together"? ?

a) he recognizes gatsby's immense wealth and points out that he is worth more money than all the others combines
b) he admires gatsby's bravery, honor, and above all optimism and faith in the american dream
c) he's trying to make gatsby feel better since he is about to go to jail
d) he's being sarcastic