Life originated on our planet

Options

A. 2 billion years ago
B. 3.7 billion year ago
C. 5 billion years ago
D. 10 billion year ago

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the time when life originated on Earth. The options provided are 2 billion years ago, 3.7 billion years ago, 5 billion years ago, and 10 billion years ago.

2. **Researching the Origin of Life**: Based on scientific studies and estimates, the origin of life on Earth is believed to have occurred approximately between 3.5 to 4 billion years ago. This is supported by various geological and fossil evidence.

3. **Analyzing the Options**:
- 2 billion years ago is too recent and incorrect.
- 3.7 billion years ago falls within the estimated range of 3.5 to 4 billion years ago.
- 5 billion years ago is too early, as Earth itself formed around 4.5 billion years ago.
- 10 billion years ago is also incorrect as it predates the formation of Earth.

4. **Selecting the Correct Answer**: Since 3.7 billion years ago is the closest option to the estimated time of life’s origin (3.5 to 4 billion years ago), it is the best choice among the provided options.

5. **Conclusion**: Therefore, the correct answer is **3.7 billion years ago**.

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