All the interacting organisms in an area together with the non-living constituents of the environment form:
Explanation:
An ecosystem is defined as a biological community of interacting organisms (biotic components) and their physical environment (abiotic components) functioning as an ecological unit. Option (2) 'Ecosystem' correctly describes this interaction. Option (1) 'Community' refers only to the interacting populations of different species within a given area, without including the abiotic factors. Option (3) 'Atmosphere' and (4) 'Soil' are examples of abiotic, non-living constituents of the environment, not the complete system of interacting living and non-living parts. Therefore, the combination of all interacting organisms and non-living constituents forms an ecosystem.