The atmosphere is held to the earth by

Options

A. gravity
B. wind
C. clouds
D. earth's magnetic field

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what holds the atmosphere to the Earth. This implies we need to identify the force or mechanism responsible for keeping the atmosphere from drifting away into space.

2. **Analyzing the Options**: The options provided are:
- A) Gravity
- B) Wind
- C) Clouds
- D) Earth's Magnetic Field

3. **Defining Gravity**: Gravity is a fundamental force of attraction that exists between any two masses. It is not limited to the Earth and objects on its surface; it also applies to the Earth and its atmosphere.

4. **Evaluating Each Option**:
- **A) Gravity**: This is the force that pulls objects toward each other. The Earth’s gravity pulls the atmosphere towards it, preventing it from escaping into space.
- **B) Wind**: Wind is the movement of air and does not have a role in holding the atmosphere to the Earth.
- **C) Clouds**: Clouds are made of water vapor and do not contribute to holding the atmosphere in place.
- **D) Earth's Magnetic Field**: While the magnetic field protects the Earth from solar winds, it does not hold the atmosphere.

5. **Conclusion**: Since gravity is the force that attracts the atmosphere towards the Earth, it is the correct answer.

6. **Final Answer**: The atmosphere is held to the Earth by **gravity**.

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