The disorder in which walls of the alveoli gets damaged , resulting in a decrease in the surface area, is called :

Options

A. Asthma
B. Allergy
C. Emphysema
D. Pneumonia

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a disorder that damages the walls of the alveoli, leading to a decrease in the surface area available for gas exchange in the lungs.

2. **Identifying the Options**: The options provided are:
- Asthma
- Allergy
- Emphysema
- Pneumonia

3. **Analyzing Each Option**:
- **Asthma**: This condition involves the trapping of air in the alveoli due to bronchoconstriction, but it does not primarily damage the alveolar walls or decrease surface area.
- **Allergy**: Allergies typically affect the upper respiratory tract and may lead to inflammation, but they do not directly damage the alveoli or decrease their surface area.
- **Emphysema**: This is a chronic lung condition that specifically damages the walls of the alveoli, leading to a significant decrease in surface area for gas exchange. This is a key characteristic of emphysema.
- **Pneumonia**: This condition involves the accumulation of fluid or pus in the alveoli, which can obstruct airflow but does not primarily damage the alveolar walls or decrease their surface area.

4. **Conclusion**: Based on the analysis, the disorder that results in damage to the walls of the alveoli and decreases the surface area is **Emphysema**.

5. **Final Answer**: The correct answer is **Emphysema**.

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