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 consistency, answers should be in all lower cased letters.
PROBLEM: Category: WITCHCRAFT 
Clue: Until Dorothy showed up, these small folks toiled as slaves for Oz' Wicked Witch of the East

SOLUTION: munchkins

PROBLEM: Category: LARGE EQUIPMENT 
Clue: For smooth travel, ballast tampers & ballast regulators keep the gravel at the right level among these

SOLUTION: railroad tracks

PROBLEM: Category: POP MUSIC 
Clue: Her self-titled debut album, which included the hit "Vision of Love", reached the top of the charts in 1990

SOLUTION:
mariah carey