What term is used for a set of organisms that interact with each other and their nonliving environment?

• A. Population
• B. Habitat
• C. Biome
• D. Ecosystem

Answer: (D)

The term "ecosystem" refers to a complex network of living organisms (such as plants, animals, and microorganisms) that interact with each other and with their nonliving environment (which includes factors like soil, water, and climate). These interactions can be in the form of food chains, nutrient cycles, and symbiotic relationships, all of which contribute to the stability and functionality of the ecosystem.

An ecosystem encompasses both the biotic components (the living organisms) and abiotic components (the nonliving environment), emphasizing their interconnectedness. For example, a forest ecosystem includes trees, animals, fungi, bacteria, and the soil, air, and water that support them.

The other terms have different meanings and focus. A population refers to a group of individuals of the same species living in a specific area. A habitat describes the specific environment where an organism lives, including the physical and biological factors that characterize it. A biome represents a larger ecological classification, usually defined by climate and geographic characteristics, encompassing multiple ecosystems. Therefore, "ecosystem" is the most comprehensive term for the set of organisms and their interactions with the environment.