It's irony because Fortunato's name means fortunate and he ends up in an unfortunate situation.
The passage is not showing up, but in general Gargantuan essentially means massive or large
The New Deal was responsible for some powerful and important accomplishments. It put people back to work. It saved capitalism. It restored faith in the American economic system, while at the same time it revived a sense of hope in the American people.
The third option seems to be the most likely, as the first and fourth options reflect conservative beliefs, and the second option isn't based upon party lines.
So the answer would be the third option.
