Final answer:
When Perseus beheaded Medusa, she was below him. Medusa was killed by Perseus as part of his quest to save his mother.
Step-by-step explanation:
When Perseus beheaded Medusa, she was below him. Medusa, a Gorgon monster with snakes for hair, was killed by Perseus as part of his quest to save his mother. Medusa's head was kept by Perseus, as it had the power to turn anyone who looked at it into stone.
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