In a food chain, the third trophic level is always occupied by

Options

A. carnivores
B. herbivores
C. decomposers
D. producers

Explanation

**Step-by-Step Solution:**

1. **Understanding Food Chain**: A food chain is a sequence that shows how energy and nutrients flow through different organisms. It starts with producers and ends with top predators.

2. **Identifying Trophic Levels**: Trophic levels are the different levels in a food chain. Each level represents a step in the flow of energy. The first trophic level consists of producers, the second level consists of herbivores, and the third level consists of carnivores.

3. **Analyzing the Example**: In the example provided, grass (a producer) occupies the first trophic level. The goat (an herbivore) that eats the grass occupies the second trophic level. The lion (a carnivore) that eats the goat occupies the third trophic level.

4. **Determining the Third Trophic Level**: Since the third trophic level is occupied by organisms that eat herbivores, it is clear that this level is filled by carnivores.

5. **Eliminating Incorrect Options**:
- Producers (like grass) occupy the first trophic level.
- Herbivores (like goats) occupy the second trophic level.
- Decomposers play a crucial role in the ecosystem but are not part of the food chain in terms of trophic levels.

6. **Conclusion**: Therefore, the third trophic level in a food chain is always occupied by carnivores.

**Final Answer**: The third trophic level is always occupied by **carnivores**.

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