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.
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Question: Category: TO SERVE 
Clue: You can serve your leftovers directly from this brand of tight-sealing food containers introduced in 1945

Answer: tupperware


Question: Category: BIG CITY LIFE 
Clue: The beginning of this regulation of land & building use dates from a 1916 New York City ordinance

Answer: zoning


Question: Category: THE WORLD AT WAR 
Clue: Unprepared for this man leading an army force over the Andes in 1817, the Spanish Empire lost Chile & Argentina

Answer:
josé de san martín