In which disease, due to flattening of tracheal vessels, alveoli are deprived of oxygen
" " Or
Name the pulmonary disease in which alveolar surface area involved in gas exchange is drastically reduced due to damage in the alveolar walls

Options

A. asthma
B. bronchitis
C. pneumonia
D. emphysema

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a disease characterized by the flattening of tracheal vessels leading to a deprivation of oxygen in the alveoli, or a pulmonary disease where the alveolar surface area for gas exchange is drastically reduced due to damage to the alveolar walls.

2. **Identifying the Diseases**: The options provided are asthma, bronchitis, pneumonia, and emphysema. We need to analyze each disease to find the correct answer.

3. **Analyzing Asthma**: Asthma is primarily an allergic reaction that causes difficulty in breathing, especially during expiration. It involves the inflammation of the bronchi due to allergens but does not specifically lead to flattening of tracheal vessels or significant damage to alveolar walls.

4. **Analyzing Bronchitis**: Bronchitis is the inflammation of the bronchi, often caused by smoking or air pollutants. While it affects the airways, it does not directly lead to the flattening of tracheal vessels or significant reduction of alveolar surface area.

5. **Analyzing Pneumonia**: Pneumonia is an acute infection that inflames the alveoli, often filled with mucus, which can obstruct gas exchange. However, it does not specifically mention the flattening of tracheal vessels or the chronic damage to alveolar walls.

6. **Analyzing Emphysema**: Emphysema is characterized by the abnormal distention of the alveoli and damage to the alveolar walls, leading to a drastic reduction in the surface area available for gas exchange. It is also associated with the flattening of tracheal vessels, which can deprive alveoli of oxygen.

7. **Conclusion**: Based on the analysis, the disease that meets the criteria of the question is emphysema. It is the correct answer as it involves both the flattening of tracheal vessels and significant damage to the alveolar walls.

**Final Answer**: Emphysema.

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