Modern birds rose in

Options

A. Palaeozoic
B. Coenozoic
C. Mesozoic
D. Archeozoic

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the era in which modern birds rose. The options provided are Paleozoic, Cenozoic, Mesozoic, and Archaeozoic.

2. **Identifying the Eons and Eras**:
- Eons are the largest time divisions in the geological time scale. The relevant eons include the Hadean, Archean, Proterozoic, and Phanerozoic.
- The Phanerozoic eon is divided into three major eras: Paleozoic, Mesozoic, and Cenozoic.

3. **Analyzing the Mesozoic Era**:
- The Mesozoic era is known for the age of dinosaurs and is divided into three periods: Triassic, Jurassic, and Cretaceous.
- The decline of dinosaurs occurred towards the end of the Jurassic period.

4. **Evolution of Birds**:
- Birds are believed to have evolved from theropod dinosaurs. This evolution is closely linked to the events occurring in the Mesozoic era.
- Specifically, modern birds are thought to have emerged during the Cretaceous period, which is the last period of the Mesozoic era.

5. **Conclusion**:
- Since modern birds evolved during the Cretaceous period, and the Cretaceous is part of the Mesozoic era, the correct answer to the question is the Mesozoic era.

**Final Answer**: Modern birds rose in the **Mesozoic era**.

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