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 consistency, answers should be in all lower cased letters.

Category: MONTREAL EXPOSE 
Clue: The Basilique Notre-Dame has one of the largest ones of these in North America; it weighs 12 tons
bell

Category: BETTER KNOWN AS.... 
Clue: Singer Helen Folasade Adu
sade

Category: SOFT "CEL" 
Clue: The University of this seaport city on the Mediterranean was founded in 1450

barcelona