The diagram represents four trophic levels in an ecosystem. Pyramid with four layers. The bottom layer shows grass with seed heads. The next layer up shows a hare, mouse, rat, grasshopper, and rabbit. The layer above that shows snakes. The top layer shows a hawk.

Which of the following BEST describes how energy flows in this ecosystem?

A. Energy flows through all the trophic levels and then back to the producers.
B. Most of the energy from the plants is transferred to the mice, grasshoppers, and rabbits because plants don't have to search for their food.
C. Birds have the most energy because energy from all the other trophic levels flows to the birds.
D. About ten percent of the energy at one trophic level is passed to the next trophic level.