In fairness, British Overseas Territories aren't strictly part of the UK. Whereas Greenland is an autonomous territory within the Kingdom of Denmark, and the Canaries are an autonomous community of Spain.
Nice quiz, though would have been nice to feature Kosciuszko to make it symmetrical, and since in this quiz we wouldn't have to spell it! Maybe it's just because I'm Australian, but the Polish sounding name would certainly be a curveball.
Is the concept really so hard to grasp? If the tallest mountain of one country happens to border another country as well, that doesn’t necessarily mean it is the highest peak of that country too.
Ooof