Read the excerpt from Echo Narcissus.Until this day, Echo's voice can be heard in the canyons of the mountains, echoing after the voices of those who pass by — "Hello … hello … Can you hear me? … hear me, hear me, hear me" with ringing tones that quickly fade.

The excerpt connects Echo’s voice to the sound that repeats and fades in mountain canyons. This is a mythological explanation of a natural phenomenon, so the best choice is “an explanation of the natural world.”

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