The function of a character foil in Greek tragedy is to reveal another character's traits through contrast. The correct answer is D.
Answer:
One of the first things Harry learns about the wizarding world is that it's dangerous to mess with goblins and flat-out mad to try and rob Gringotts, but Voldemort manages to attempt this a few chapters later, offscreen. Then Book 7 rolls around.The high-security vaults are guarded by dragons.
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