Question

as energy flows through ecosystems, atoms and molecules cycle among
a. both the living and nonliving components of the biosphere.
b. only the living components of the biosphere.
c. neither the living nor the nonliving components of the biosphere.
d. only the nonliving components of the biosphere.

Explanation:

In ecosystems, biogeochemical cycles (like carbon, nitrogen cycles) involve atoms and molecules moving between living (biotic) and nonliving (abiotic) components (e.g., plants take up nutrients from soil, release them back). So atoms/molecules cycle among both. Option A matches this concept.

Answer:

A. both the living and nonliving components of the biosphere.