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: LET'S GET DOWN TO BUSINESS 
Clue: I can get it for you wholesale at this warehouse chain that merged with Price Club in 1993

SOLUTION: costco

PROBLEM: Category: ORGANIZATIONS 
Clue: This service "Club" has a 4-way test of things they think, say & do, including "Will it be beneficial to all concerned?"

SOLUTION: the rotary club

PROBLEM: Category: ONE VOWEL ONLY 
Clue: A twisting tool that's "thrown into" a situation to mess it up

SOLUTION:
a wrench