Secondary producers are:-

Options

A. Herbivores
B. Producers
C. Carnivores
D. None of the above

Explanation

### Step-by-Step Solution:

1. **Understanding Producers**: In an ecosystem, producers are organisms that can produce their own food through processes like photosynthesis. The primary producers are typically plants, which convert sunlight into energy.

2. **Identifying the Role of Producers**: Producers form the base of the food chain. They are essential because they provide energy and nutrients to other organisms (consumers) in the ecosystem.

3. **Defining Secondary Producers**: The term "secondary producers" is often misunderstood. In ecological terms, secondary producers usually refer to organisms that consume primary producers. However, in strict definitions, secondary producers do not exist as a separate category because producers are primarily plants.

4. **Conclusion**: Since plants are the only organisms that can produce their own food and are not dependent on other organisms, we conclude that there are no secondary producers in the ecosystem. The only producers are the primary producers, which are the plants.

### Final Answer:
Secondary producers do not exist as a separate category; the only producers in an ecosystem are primary producers, which are plants.

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