Neat quiz! Could you accept Mt. Kosciuszko for Australia? After reading I know Mawson peak is actually higher, but it's in an external territory. Doing the same for, say, Denmark and the Netherlands would put their highest points in Greenland and Saba, which would be confusing. Kosciuszko is usually what people think of as the highest place in Australia, which is evidenced by the fact that no one has gotten it right yet.