One country flag has been replaced with a question mark. Based on the theme of this puzzle, can you figure out which flag it is? The final answer to this puzzle is 10 letters long.
Hint 1: You may or may not have realized this but it's...
...1 vs 1.
Since there is a big bounty now, let me give you another hint.
Hint 2:
Besides identifying the flags, you gotta apply some knowledge unrelated to geography.