What term is used to describe all living organisms that inhabit a particular environment?

The term that describes all living organisms that inhabit a particular environment is "biotic factors." This term specifically refers to the biological aspects of an ecosystem, which includes plants, animals, fungi, and microorganisms. These organisms interact with one another and their physical surroundings, playing vital roles in the ecosystem's structure and function.

Understanding biotic factors is essential because they are interconnected and influence various ecological processes, such as food webs, nutrient cycling, and habitat formation. In contrast, the other options pertain to different aspects of an ecosystem: abiotic factors refer to the non-living components like climate and soil, ecological factors encompass the relationships among living organisms and their environment, and environmental factors can include both biotic and abiotic influences, but do not solely focus on living organisms.