The first seed plants appeared during

Options

A. Cretaceous
B. Carboniferous
C. Devonian
D. Silurian.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks when the first seed plants appeared, providing four options: Cretaceous, Carboniferous, Devonian, and Silurian.

2. **Understand the Timeframes**:
- Cretaceous: This era is known for the dominance of flowering plants and dinosaurs, occurring around 145 to 66 million years ago.
- Carboniferous: This era is characterized by the extensive development of coal-forming forests, occurring around 359 to 299 million years ago.
- Devonian: Known as the "Age of Fishes," this era occurred around 419 to 359 million years ago and is significant for the emergence of early land plants, including the first seed plants.
- Silurian: This era, occurring around 443 to 419 million years ago, saw the development of early vascular plants but not seed plants.

3. **Identify the First Seed Plants**: According to fossil records, the first seed plants, such as Alkensia polymorpha, appeared during the Devonian period, around 400 million years ago.

4. **Eliminate Incorrect Options**:
- Cretaceous is too late for the first seed plants.
- Carboniferous is also too late, as seed plants emerged earlier.
- Silurian is too early, as the first seed plants did not appear until the Devonian.

5. **Conclusion**: The first seed plants appeared during the Devonian era.

**Final Answer**: The first seed plants appeared during the Devonian era.

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