Mountain sickness is due to

Options

A. Colder atmosphere
B. Higher humidity
C. Winds
D. Rarefactin of air.

Answer

**Step-by-Step Solution:**

1. **Understanding Mountain Sickness**: Mountain sickness, also known as acute mountain sickness (AMS), occurs when a person ascends to high altitudes too quickly. It is primarily caused by a lack of oxygen at these altitudes.

2. **Analyzing the Options**: The question provides four options:
- A) Colder temperature
- B) Higher humidity
- C) Winds
- D) Rarefaction of the air

3. **Evaluating Each Option**:
- **Colder Temperature**: While temperatures are indeed lower at higher altitudes, this is not the primary cause of mountain sickness. Therefore, this option is incorrect.
- **Higher Humidity**: Humidity levels do not significantly change at high altitudes in a way that would cause mountain sickness. Thus, this option is also incorrect.
- **Winds**: Wind conditions may vary at high altitudes, but they do not directly cause mountain sickness. Hence, this option is incorrect as well.
- **Rarefaction of the Air**: As altitude increases, the air becomes less dense (rarefied), leading to lower oxygen levels. This lack of oxygen is the primary reason for mountain sickness. Therefore, this option is correct.

4. **Conclusion**: The correct answer to the question "Mountain sickness is due to" is **D) Rarefaction of the air**.

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