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: WORLD HISTORY 
Clue: In a 1918 treaty, this country gave up Ukraine but soon recovered it

Answer: russia


Question: Category: LEADING MEN 
Clue: In 2006 this country's President Ahmadinejad admitted it was enriching uranium

Answer:
iran