Assertion : At higher peaks of mountains, people suffer from high altitude sickness (sluggish feeling, breathlessness etc.) due to lesser oxygen intake at each breather
Reason : Air at sea level is dense because it is compressed by the mass of the air above it. The atmospheric pressure at higher peaks of mountains is lower causing the air at those heights to be much less dense than at sea level.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that at higher peaks of mountains, people suffer from high altitude sickness due to lesser oxygen intake. This is true because as altitude increases, the atmospheric pressure decreases, leading to a lower concentration of oxygen in the air.

2. **Understanding the Reason**: The reason provided explains that air at sea level is dense due to the mass of air above it, which compresses the air. This is also true. At sea level, the weight of the air above compresses the air below, resulting in higher density and more oxygen availability.

3. **Connecting the Assertion and Reason**: While both the assertion and reason are true, the reason does not directly explain the assertion. The assertion focuses on the physiological effects of lower oxygen availability at high altitudes, while the reason describes the physical properties of air density at sea level.

4. **Conclusion**: Since both the assertion and reason are true but the reason does not adequately explain the assertion, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

**Final Answer**: Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

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