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: FLAGS
Clue: Christopher Columbus' flag bore a cross with their initials on either side

SOLUTION: ferdinand & isabella

PROBLEM: Category: "D" IN SCIENCE
Clue: Sharks first inhabited the waters during this period of the Paleozoic era named for an English county

SOLUTION: devonian

PROBLEM: Category: HISTORIC NAMES
Clue: When you turn on a light bulb, you can thank him; he invented it

SOLUTION:
thomas edison