An ecosystem is

  1. all the plants in a field
  2. one species in an area
  3. a food chain
  4. a community and its environment interacting together
Answer

D) a community and its environment interacting together

Definition of ecosystem. O Level Biology · Topic 19 Relationships of Organisms with One Another and with the Environment · 19.3 Ecosystems and biodiversity

Biology MCQ · More O Level Biology: Organisms and the Environment MCQs · Practise