Ancestral amphibians were tetrapods that evolved during

Options

A. Devonian
B. carboniferous
C. cretacous
D. jurassic

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the time period during which ancestral amphibians, which are tetrapods, evolved.

2. **Identifying the Options**: The options provided are:
- Devonian
- Carboniferous
- Cretaceous
- Jurassic

3. **Analyzing the Evolution of Tetrapods**:
- Tetrapods are vertebrates that evolved from lobe-finned fishes.
- The evolution of tetrapods began approximately 400 million years ago.

4. **Determining the Correct Period**:
- The Devonian period is known for the emergence of early tetrapods. Therefore, it is the correct answer.
- The Carboniferous period primarily saw the evolution of more diverse terrestrial life but not the initial evolution of tetrapods.
- The Cretaceous period is characterized by the extinction of dinosaurs, which occurred much later than the evolution of tetrapods.
- The Jurassic period is known as the golden age of dinosaurs, which also occurred after the evolution of tetrapods.

5. **Conclusion**: Based on the analysis, the correct answer is the **Devonian period**.

**Final Answer**: Ancestral amphibians were tetrapods that evolved during the **Devonian** period.

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