CardinalSin and BZ2YYZ are both quite right here. It's the United Kingdom of Great Britain and Northern Ireland. It says so right there on the front of my passport.
Czechia is accepted as a valid answer for the Czech Republic. However, I do understand the ambiguity, so I have added a caveat as per your suggestion. Thanks
Actually the naming convention on Jetpunk always uses Czech Republic as far as I'm aware. Countries of the World uses at the very least and that's supposed to be the standard.
Hope this helps you understand why I added UK to this quiz!