TASK DEFINITION: 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.
PROBLEM: Category: ARE YOU A BETTING MAN? 
Clue: C'mon, one more cherry!  Bally's Las Vegas became the first hotel with a $1,000 one of these

SOLUTION: a slot machine

PROBLEM: Category: THE YOU-NIVERSE 
Clue: Containing 33 vertebrae, it's also known as the vertebral column

SOLUTION: the spine

PROBLEM: Category: WHAT'S THE USE 
Clue: A Geiger counter is used primarily to measure this

SOLUTION:
radiation