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.
--------
Question: Category: MOZART & FRIENDS 
Clue: Mozart wrote a lovely motet for Venanzio Rauzzini, one of these specially treated singers

Answer: a castrato


Question: Category: JORDAN 
Clue: Jordan lost the city of Jerusalem & the territory known as the West Bank during a war in this year

Answer: 1967


Question: Category: HEAVY MACHINERY 
Clue: By definition it's a machine that gives a surface an even degree of slope

Answer:
grader