Why is a shell considered to be biotic? because it is found in the biosphere because it was alive because it came from something living because it is not living

C, because it came from something living

Explanation: The definition of biotic is of or relating to an environmental factor that is living or that came from something that was once living. Specifically, on the part where it says that it "came from something that was once living". Thus, making it living or biotic.

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