Which is a component of mountain sickness ?

Options

A. Difficult breathing
B. Nausea and headache
C. Bluish tongue
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Mountain Sickness**: Mountain sickness, also known as altitude sickness, occurs when individuals ascend to high altitudes too quickly. At higher elevations, the atmospheric pressure decreases, leading to lower oxygen levels.

2. **Recognizing Symptoms**: The symptoms of mountain sickness can include:
- Dizziness
- Headache
- Nausea
- Vomiting
- Difficulty in breathing
- Bluish tongue (cyanosis)

3. **Analyzing the Options**: The question asks for a component of mountain sickness. The symptoms listed above are all associated with this condition.

4. **Identifying the Correct Answer**: Since all the symptoms mentioned (difficulty in breathing, nausea, headache, and bluish tongue) are components of mountain sickness, the correct answer is that all of the above options are correct.

5. **Conclusion**: Therefore, the answer to the question is that all of the mentioned symptoms are components of mountain sickness.

**Final Answer**: Option 4: All of the above.

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