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: WHAT SHOULD I "DU"?
Clue: A philosophical system that seeks to explain all phenomena in terms of 2 distinct principles

SOLUTION: dualism

PROBLEM: Category: ISLANDS
Clue: 3,414-foot-high Carrantuohill west of Killarney is the highest peak on this island

SOLUTION: ireland

PROBLEM: Category: THE GIANTS
Clue: If you're visiting the rocky promontory called the Giant's Causeway, you're traveling on this island

SOLUTION:
ireland