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.

Category: LANDMARKS 
Clue: Some of its pieces, which weighed up to 50 tons, were quarried at Marlborough Downs, about 20 miles away
stonehenge

Category: VOLCANOES 
Clue: The 5 highest volcanoes on Earth are located in these mountains
andes

Category: COMPUTER HISTORY 
Clue: IBM engineer Dave Bradley is called the father of this multi-key combination

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