animals. rocks and water. living and nonliving things. populations of plants and animals.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: An ocean, a forest, and a grassy meadow are each examples of a complete ecosystem. Complete ecosystems contain only
Possibilities:
- animals.
- rocks and water.
- living and nonliving things.
- populations of plants and animals.

living and nonliving things.