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: DOUBLE TALK 
Clue: A short ballet skirt, or South African Archbishop Desmond

SOLUTION: tutu

PROBLEM: Category: "E" BAY 
Clue: Thinking green, biologist Ernst Haeckel coined this term for the way animals interact with the environment

SOLUTION: ecology

PROBLEM: Category: LINES 
Clue: Not George Hamilton, it's the term in geometry for the straight line seen here

SOLUTION:
tangent