Question

Which statement describes matter flowing from a nonliving part of the ecosystem to a living part, then back to a nonliving part?

A.
Carbon dioxide in air is taken up by trees, and then it becomes organic matter in soil.
B.
Ground beetles on the ground are eaten by birds, which die and become organic matter in soil.
C.
Fungi in soil are eaten by nematodes, which are then hunted by centipedes.
D.
Carbon in organic matter is broken down by bacteria, and then it is eaten by nematodes.

Answer 1

Option A describes matter flowing from a nonliving part of the ecosystem (air) to a living part (trees) and then back to a nonliving part (soil). The carbon dioxide in the air is taken up by the trees and then becomes organic matter in the soil as the tree dies and decomposes. Therefore, option A is the correct statement.