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: DOUBLE DOUBLE LETTERS 
Clue: A gathering at which Pete Seeger & Joan Baez, or an owl & a goat might sing

SOLUTION: hootenanny

PROBLEM: Category: POTPOURRI 
Clue: Country in which you'd find the Book of Kells

SOLUTION: ireland

PROBLEM: Category: BACKWORDS 
Clue: Liam likes to sort this

SOLUTION:
mail