Deer eats only plant products and so, is called _________.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that deer eats only plant products. We need to identify the category of animals that consume only plants.

2. **Identifying Animal Categories**: Animals can be classified based on their diet into three main categories:
- **Herbivores**: Animals that eat only plants and plant products.
- **Carnivores**: Animals that eat other animals.
- **Omnivores**: Animals that eat both plants and animals.
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