_________ are primary consumers.

Explanation

**Step-by-Step Solution:**

1. **Identify Primary Consumers**: Primary consumers are organisms that consume primary producers (plants). They are typically herbivores, meaning they primarily eat plants.

2. **Understanding the Trophic Levels**: In an ecosystem, the first trophic level consists of primary producers (plants), and the second trophic level consists of primary consumers (herbivores).

3. **Examples of Primary Consumers**: A common example of a primary consumer is the grasshopper. Grasshoppers feed on plants, making them herbivores and placing them in the category of primary consumers.

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