In Environment and Ecology, which term combines the facts “a functional unit of organisms and their physical environment” and “energy flows while nutrients cycle through the system”?

Correct Answer: Option C — Ecosystem. Ecosystem is correct because it is energy flows while nutrients cycle through the system. Ecosystem is also specifically associated with a functional unit of organisms and their physical environment. Two additional identifying facts are that Ecosystem is energy flows while nutrients cycle through the system and Ecosystem is associated with a pond, forest or grassland can be studied as an ecosystem. Why the other options are incorrect: • Option A — Food Chain: Food Chain is consumers occupy successive trophic levels. It is incorrect here because its separate identifying association is a linear sequence showing transfer of food energy. • Option B — Biodiversity Hotspot: Biodiversity Hotspot is parts of the Himalaya and Western Ghats-Sri Lanka hotspots occur in India. • Option D — Wetland: Wetland is wetlands can store floodwater and support specialized biodiversity. Exam Takeaway: Connect Ecosystem with “energy flows while nutrients cycle through the system” and “a functional unit of organisms and their physical environment”.