Each step in a food web or chain.

• A. Food chain
• B. Detritovore
• C. Food web
• D. Trophic level

Answer: (D)

Trophic level describes the position of organisms in the flow of energy through an ecosystem. Each step in a food chain or food web corresponds to a different trophic level, with producers at the base, followed by primary consumers, secondary consumers, and so on. This framing helps explain how energy moves through the system and why only a portion of it is transferred to the next level. A food chain is just one linear path of energy transfer, while a food web is a network of many interconnected paths. Detritivores, on the other hand, feed on detritus and represent a different energy pathway rather than a specific step in the main energy transfer sequence.