An ecosystem is all of the biotic and abiotic factors in a given area.
This definition encompasses not only the living organisms (biotic factors) such as plants, animals, and microorganisms but also the non-living components (abiotic factors) like water, air, soil, and climate. An ecosystem functions as a complex network where these factors interact and influence one another. While the other options focus solely on organisms or large areas, this description provides a more comprehensive understanding of what an ecosystem truly is, highlighting the intricate relationships and dependencies that exist within a defined space.