Can someone answer this for me?

A!

Explanation: All biological organisms play a part in the earth's ecosystem, but consumers get energy from eating other organisms and producers make energy on their own. Grass is a producer, a self-sustaining organism that obtains its energy from the sun. In the process, it introduces new organic substances into the food chain and plays a key role for consumers. Grass forms the basis of the food chain because of this ability.

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: