The reason for spilling out the blood from the nose of mountaineers is :

Options

A. low atmospheric pressure and low blood pressure of the body
B. high atmospheric pressure and low blood presure of the body
C. low atmospheric pressure and high blook pressure of the body
D. none of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Situation**: When mountaineers ascend to high altitudes, they experience a change in atmospheric pressure. At higher altitudes, the atmospheric pressure is significantly lower than at sea level.

2. **Effect of Low Atmospheric Pressure**: As the mountaineers climb, the decrease in atmospheric pressure can lead to a condition known as hypoxia, where there is insufficient oxygen available. This can cause various physiological responses in the body.

3. **Blood Pressure Dynamics**: While the atmospheric pressure decreases, the blood pressure in the body may remain high due to the body’s compensatory mechanisms to maintain oxygen supply to vital organs. This mismatch between low external pressure and high internal blood pressure can lead to the rupture of small blood vessels in the nose.

4. **Resulting Condition**: The rupture of these blood vessels can cause blood to spill out from the nose, a condition commonly observed in mountaineers at high altitudes.

5. **Conclusion**: Therefore, the reason for the spilling out of blood from the nose of mountaineers is primarily due to low atmospheric pressure combined with high blood pressure in the body.

**Final Answer**: The correct reason for spilling out blood from the nose of mountaineers is: low atmospheric pressure and high blood pressure of the body.

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