Assertion : Emphysema is the permanent abnormal inflation of air space of terminal bronchioles or alveolar sacs.
Reasons : Destruction of pulmonary tissues specially alveolar septa and flattening of alveolar ducts occur in emphysema.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true and reason is not the correct explanation of assertion
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that emphysema is characterized by the permanent abnormal inflation of air spaces in the terminal bronchioles or alveolar sacs.
- This means that in emphysema, the air spaces in the lungs become enlarged and do not return to their normal size, which is a key feature of the disease.

2. **Analyzing the Reason**:
- The reason provided explains that emphysema involves the destruction of pulmonary tissues, particularly the alveolar septa, and the flattening of alveolar ducts.
- This destruction leads to a decrease in the number of pulmonary capillaries, which can increase pulmonary vascular resistance and lead to complications such as pulmonary hypertension.

3. **Evaluating the Correctness**:
- Both the assertion and the reason are correct statements regarding emphysema.
- The assertion correctly describes the condition of emphysema, while the reason accurately describes the pathological changes that occur in the lungs due to emphysema.

4. **Determining the Relationship**:
- Although both statements are correct, the reason does not directly explain the assertion. The assertion focuses on the abnormal inflation of air spaces, while the reason discusses the destruction of lung tissue and its consequences.
- Therefore, while the reason provides important information about the disease, it does not serve as a direct explanation for the assertion.

5. **Conclusion**:
- The assertion is true, and the reason is also true, but the reason is not the correct explanation for the assertion.

### Final Answer:
- **Assertion**: True
- **Reason**: True
- **Explanation**: The reason does not correctly explain the assertion.

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