Amphibians were dominant during ____ period.

Options

A. Carboniferous
B. Silurian
C. Ordovician
D. Cambrian

Explanation

**Step-by-Step Solution:**

1. **Understanding Geological Eras**: The geological history of Earth is divided into three main eras: Paleozoic, Mesozoic, and Cenozoic. Each era has distinct periods that are characterized by different dominant life forms.

2. **Identifying the Paleozoic Era**: The Paleozoic era is particularly significant for the diversification of animals. It is further divided into several periods, including the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian.

3. **Examining Each Period**:
- **Cambrian Period**: Known for the emergence of many invertebrates.
- **Ordovician Period**: Characterized by the evolution of more invertebrates.
- **Silurian Period**: The first vertebrates appeared, primarily jawless fish.
- **Devonian Period**: Known as the "Age of Fishes" due to the dominance of fish species.
- **Carboniferous Period**: This is where amphibians emerged as dominant life forms, evolving from lobe-finned fishes that adapted to life on land.
- **Permian Period**: Marked the evolution of reptiles, but amphibians were still significant.

4. **Conclusion**: The period during which amphibians were dominant is the Carboniferous Period, as they evolved from fish and adapted to both aquatic and terrestrial environments.

**Final Answer**: Amphibians were dominant during the Carboniferous period.

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