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: LEGENDS 
Clue: She abducted Lancelot when he was a baby & kept him on an island
the lady of the lake

Category: WORLD RELIGION 
Clue: The world's largest religious structure, Angkor Wat in Cambodia, was built to honor this preserver deity
vishnu

Category: EUROPE 
Clue: Its use dates back to 1360; on January 1, 2002 Belgium dropped it but Switzerland kept it

the franc