DPESTICIDESSWEwhat is a man-made ecosystem but you get the idea

Ecosystem Definition
The simplest definition of an ecosystem is that it is a community or group of living organisms that live in and interact with each other in a specific environment.
For instance, tropical forests are ecosystems made up of living beings such as trees, plants, animals, insects and micro-organisms that are in constant interaction between themselves and that are affected by other physical (sun, temperature) or chemical (oxygen or nutrients) components.

The answer would be c