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: QUEEN ELIZABETH II 
Clue: It's Queen Elizabeth's official London residence
[EX A]: buckingham palace

[EX Q]: Category: BIOLOGY 
Clue: Like mushrooms, molds belong to this group of organisms that lack chlorophyll
[EX A]: fungi

[EX Q]: Category: CITIES 
Clue: This capital is located in the historical region of New Castile
[EX A]:
madrid