Final answer:
The step in the food chain known as a herbivore is the Primary Consumer.
Step-by-step explanation:
The step in the food chain that is known as a herbivore is the Primary Consumer. Herbivores are organisms that primarily consume plants for their nutrition.
For example, in a grassland ecosystem, a primary consumer could be a rabbit or a deer that feeds on plants such as grass and leaves.
Unlike herbivores, producers (option A) are organisms that can produce their own food through processes like photosynthesis, decomposers (option D) are organisms that break down dead plants and animals, and primary consumers (option C) are organisms that directly consume producers (plants) for their nutrition.
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