The answer should be the first one : a return to normalcy and isolationism. The reason for this is because they wanted to keep out of foreign affairs from there on out. Obviously that did not work out as well as hoped since Americans were forced into the 2nd World War as well as the Korean and Vietnamese wars. Hope this helps!
It’s B, because if you think about it it’s the only one that make sense
Personally, I think it's because it was simple and free entertainment. Given that there wasn't a taboo around death and watching others die, and it actually being encouraged, like how it was in Anciient Rome, I'd say a lot of people would actually at least try out visiting a gladiatorial contest.
