The question about the founding date is highly misleading. The Republic of China was indeed founded in 1912 and the country we generally think of as Taiwan indeed offically claims to be the Republic of China (according to its constitution, the whole of the pre-war Chinese republic, most of which is today's PRC, still belongs to it, with the assumption that the continental part will return unter the democratic republic's sovereignty as soon as the Maoist rebels are defeated). But in practical terms, the political and social entity we know as Taiwan came to being after the second world war. Conversely, one may be excused for thinking that what we call China was actually founded in 1912, since the PRC claims to be the legal successor of the pre-war Republic of China and shares the vast majority of its area. I would guess that in both cases, the clash between theory and practice is too prominent and the best solution would be to leave this question out.
JetPunk considers Taiwan a country and although world disputes are still ongoing, Taiwan considers itself the Republic of China and it was founded by them in 1912. So either if you consider it a country or not anyways, the state/country of Taiwan was founded in 1912 by the nationalists. If you want me to add a caveat saying that these issues are ongoing, I will, but I personally side with JetPunk in this and will keep the questions the same.
I understand your reasons, and of course feel free to leave it as it is (it is you quiz after all). I just think that in this particular case the jetpunk convention clashes with common sense, since none of the founding fathers of the Republic of China in 1912 would see himself as "founding Taiwan", if you know what I mean. If I were you, I would perhaps replace the question with "Its current name comes from 1912" or something like that. But again, your quiz, your rules :)
GDP question is also wrong, I think you mean GDP per capita, or else China has a much larger GDP, one of the highest in the world. Common mistake, nice quiz though!
:)
Which (of these two countries) has the second highest GDP? The answer being Taiwan.
OR:
Which has the second highest GDP (in the world)? The answer being China.