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.

Category: DIAMONDBACKS 
Clue: Of 8, 16 or 28, the length in feet of the longest diamondback ever recorded (not counting Randy Johnson)
8 feet

Category: GREAT BRITS 
Clue: He joined the British navy at age 12 & died at the Battle of Trafalgar 35 years later
lord nelson

Category: DEMOCRACY 
Clue: In 1996 the Supreme Court struck down 4 of these areas created to allow black & hispanic representation

congressional districts