At the time of origin of life, the surface temperature of earth was

Options

A. `100^(@)C`
B. `50-60^(@)C`
C. `35-40^(@)C`
D. `10-15^(@)C`

Answer

To determine the surface temperature of Earth at the time of the origin of life, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Time Frame**: The origin of life on Earth is estimated to have occurred between 3.5 to 4 billion years ago. This is crucial for understanding the environmental conditions of that time.

2. **Analyzing Early Earth Conditions**: During the early days of Earth, the planet was still forming and undergoing significant geological activity. This included collisions with rocky debris, which contributed to a higher surface temperature.

3. **Formation of Oceans**: As the Earth cooled over time, oceans began to form. However, at the time of the origin of life, the temperature was still relatively high compared to present-day conditions.

4. **Temperature Estimation**: Based on scientific estimates, the surface temperature of Earth at the time of the origin of life is believed to have been approximately between 50 to 60 degrees Celsius. This is significantly higher than the current average surface temperature.

5. **Evaluating Options**: Given the options provided:
- 100 degrees Celsius (incorrect)
- 50 to 60 degrees Celsius (correct)
- 30 to 40 degrees Celsius (incorrect)
- 10 to 15 degrees Celsius (incorrect)

6. **Conclusion**: The correct answer is that at the time of the origin of life, the surface temperature of Earth was approximately 50 to 60 degrees Celsius.

### Final Answer:
The surface temperature of Earth at the time of the origin of life was approximately **50 to 60 degrees Celsius**.

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