You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

[EX Q]: Category: PRESIDENTIAL LIBRARIES 
Clue: Opened in 1971, his presidential library is the farthest south
[EX A]: lyndon johnson

[EX Q]: Category: COUNTRIES' HIGHEST PEAKS 
Clue: These 2 nations, one an island, have highest peaks with the same name; they also share a common European culture
[EX A]: greece & cyprus

[EX Q]: Category: EUROPE 
Clue: The Soviet army was welcome in this capital in May of '45 but unwelcome in August '68
[EX A]:
prague