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 priducer
C. tertiary consumer
D. secondary consumer

Explanation

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

### Step-by-Step Solution:

1. **Identify the Producers**: The first step in any food chain is the producers. These are typically plants or autotrophs that fix carbon dioxide through photosynthesis.

2. **Understand Trophic Levels**: In a food chain, organisms are categorized into different trophic levels:
- **Producers** (Trophic Level 1)
- **Primary Consumers** (Trophic Level 2) - These are herbivores that eat producers.
- **Secondary Consumers** (Trophic Level 3) - These are carnivores that eat primary consumers.
- **Tertiary Consumers** (Trophic Level 4) - These are carnivores that eat secondary consumers.

3. **Trace the Carbon Atoms**: The question states that the carbon atoms fixed by producers have passed through three species. This means:
- The first species would be the **Primary Consumer** (Trophic Level 2).
- The second species would be the **Secondary Consumer** (Trophic Level 3).
- The third species would be the **Tertiary Consumer** (Trophic Level 4).

4. **Determine the Trophic Level of the Last Species**: Since the carbon atoms have passed through three species, the last species in this chain would be at Trophic Level 4, which is the **Tertiary Consumer**.

5. **Conclusion**: Therefore, the trophic level of the last species through which the carbon atoms have passed is that of a **Tertiary Consumer**.

### Final Answer:
The trophic level of the last species would be **Tertiary Consumer**.

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