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.
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Question: Category: MUSICAL THEATER 
Clue: In France, this musical was known as "Brillantine"; in Mexico, it was "Vaselina"

Answer: grease


Question: Category: DEMOGRAPHICS 
Clue: In 2005 the World Health Organization appropriately decided to stop hiring people who do this

Answer: smoke


Question: Category: SCIENTISTS 
Clue: On the front lines during WWI, she drove ambulances that she had helped equip with x-ray machines

Answer:
marie curie