Age of mammals and birds is

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the age of mammals and birds.

2. **Understand Geological Eras**: Familiarize yourself with the geological time scale, which includes different eras: Archezoic, Paleozoic, Mesozoic, and Cenozoic.

3. **Determine the Era of Mammals and Birds**:
- The Cenozoic era is known as the "Age of Mammals" because it is during this time that mammals and birds became the dominant terrestrial vertebrates.
- The Cenozoic era follows the Mesozoic era, which was known as the "Age of Reptiles."

4. **Eliminate Incorrect Options**:
- **Mesozoic Era**: Known for the dominance of reptiles, particularly during the Jurassic period.
- **Archezoic Era**: This is referred to as the "dawn of life," which does not pertain to mammals and birds.
- **Paleozoic Era**: Known as the "era of ancient life," primarily dominated by amphibians and fishes.

5. **Conclude the Correct Answer**: Based on the above analysis, the correct answer is the Cenozoic era, which is option number 2.

**Final Answer**: The age of mammals and birds is the Cenozoic era (Option 2).

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