Altitude sickness occurs at high mountains. This sickness have symptoms like

Options

A. nausea
B. fatigue
C. heart palpitations
D. all of these

Answer

### Step-by-Step Solution:

1. **Understanding Altitude Sickness**: Altitude sickness occurs when individuals ascend to high altitudes, typically above 2,500 meters (8,200 feet), where the atmospheric pressure is significantly lower than at sea level.

2. **Effects of Low Atmospheric Pressure**: At high altitudes, the lower atmospheric pressure results in a decreased availability of oxygen. This means that there is less oxygen available for the body to use.

3. **Oxygen Deprivation**: The reduced oxygen concentration in the air leads to a decrease in the amount of oxygen that enters the bloodstream. Consequently, the body struggles to obtain the necessary oxygen for its metabolic functions.

4. **Symptoms of Altitude Sickness**: Due to the lack of sufficient oxygen, various symptoms can manifest. Common symptoms include:
- **Nausea**: A feeling of sickness with an inclination to vomit.
- **Fatigue**: A state of extreme tiredness or lack of energy.
- **Heart Palpitations**: An increase in heart rate as the body attempts to compensate for the low oxygen levels.

5. **Conclusion**: Therefore, the symptoms of altitude sickness include nausea, fatigue, and heart palpitations.

### Final Answer:
The symptoms of altitude sickness include nausea, fatigue, and heart palpitations.

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