If the carbon atoms fixed by producers already have passed through three species, the trophic level of the last species would be

Options

A. scavenger
B. tertiary producer
C. tertiary consumer
D. secondary consumer.

Explanation

To determine the trophic level of the last species that the carbon atoms have passed through, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Trophic Levels**:
- The first trophic level is occupied by **producers** (e.g., plants, phytoplankton).
- The second trophic level is occupied by **primary consumers** (herbivores that eat producers).
- The third trophic level is occupied by **secondary consumers** (carnivores that eat primary consumers).
- The fourth trophic level is occupied by **tertiary consumers** (carnivores that eat secondary consumers).

2. **Analyze the Question**:
- The question states that the carbon atoms fixed by producers have passed through **three species**. This means they have moved through three different trophic levels.

3. **Determine the Last Species**:
- If the carbon has passed through three species, we can count:
- The first species (1st trophic level) is the **producer**.
- The second species (2nd trophic level) is the **primary consumer**.
- The third species (3rd trophic level) is the **secondary consumer**.
- Therefore, the last species, which is the one that has consumed the carbon atoms after passing through three species, would be the **tertiary consumer** (4th trophic level).

4. **Conclusion**:
- The trophic level of the last species is the **tertiary consumer**.

### Final Answer:
The trophic level of the last species would be **tertiary consumer**.

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