Life originated in the

Options

A. precambrian era
B. palaeozoic era
C. mesozoic era
D. coenozoic era

Answer

**Step-by-Step Solution:**

1. **Understanding Geological Time Scale**: The geological time scale is divided into eons, eras, and periods. For this question, we will focus on the eras since the options provided are in that format.

2. **Identifying the Eras**: The main eras in the geological time scale are:
- Cenozoic Era
- Mesozoic Era
- Paleozoic Era
- Pre-Cambrian Era

3. **Analyzing Each Era**:
- **Cenozoic Era**: This is the most recent era, characterized by the Ice Age and the evolution of modern humans. Since life did not originate here, we can eliminate this option.
- **Mesozoic Era**: Known as the age of dinosaurs and the rise of mammals and flowering plants. This era is also not where life originated, so we can eliminate this option as well.
- **Paleozoic Era**: This era saw the appearance of amphibians, insects, and reptiles. While it was significant for the evolution of life, it is not where life first originated.
- **Pre-Cambrian Era**: This is the earliest era in the geological time scale, where we find the oldest fossils, including prokaryotic and eukaryotic organisms. This indicates that life first originated during this time.

4. **Conclusion**: Based on the analysis, the correct answer is that life originated in the **Pre-Cambrian Era**.

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