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.

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

Example Input: Category: FOREIGN TRAVEL 
Clue: Though its slangy name suggests it goes behind, wear this in front to guard your valuables against theft
Example Output: a fanny pack

Example Input: Category: THE SCIENCE OF COLOR 
Clue: In violet, this distance is a short 3,800 to 4,500 angstrom units
Example Output:
wavelength