Trace Matter in Ecosystems Practice Test

Use the ecosystem model below. Arrows show matter moving and labels identify the matter: CO$_2$ in air → shrub; shrub matter → rabbit → hawk; dead organisms/waste → decomposers → nutrients in soil → shrub; decomposers → CO$_2$ in air. The model shows matter cycling through ecosystems.

Which statement is supported by the model as evidence that matter cycles (rather than moving one-way and stopping)?

Refer to the ecosystem model: CO$_2$ in air → corn plant; corn plant matter → mouse → owl; dead organisms/waste → decomposers → nutrients in soil → corn plant; decomposers → CO$_2$ in air. The arrows represent matter movement and labels name the matter. This model shows matter cycling through ecosystems.

Which path best traces matter that starts as nutrients in soil and later becomes part of an owl?