Question

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Explanation:

Nitrogen recycling in ecosystems is mainly done by decomposers, which break down organic matter. Bacteria are decomposers that convert nitrogen - containing compounds in dead organisms (like frogs, snakes, grasshoppers) and waste into forms usable by producers (like grasses). Frogs, snakes, and grasshoppers are consumers or producers and don't have the primary role of nitrogen recycling. So bacteria are necessary for nitrogen recycling.

Answer:

bacteria