Occupational diseases are characterised by fibrosis of lungs in

Options

A. Upper part
B. Lower part
C. Base of lungs
D. Mediastinum

Answer

### Step-by-Step Solution:

1. **Understanding Occupational Diseases**: Occupational diseases are health issues that arise due to exposure to harmful substances in the workplace. In the context of respiratory disorders, these diseases often result from inhaling dust, chemicals, or other particulates.

2. **Identifying the Cause**: In industries such as stone cutting or mining, workers are frequently exposed to silica dust. This dust can accumulate in the lungs over time, leading to respiratory issues.

3. **Understanding Fibrosis**: Fibrosis refers to the formation of excess fibrous connective tissue in an organ, which can lead to scarring and damage. In the lungs, this can impair function and lead to chronic respiratory problems.

4. **Locating the Affected Area**: The question asks which part of the lungs is primarily affected by fibrosis due to occupational exposure. Research and clinical observations indicate that the upper parts of the lungs are most commonly impacted by inhaled dust and silica.

5. **Conclusion**: Based on the information, the correct answer to the question is that occupational diseases characterized by fibrosis of the lungs primarily affect the **upper part** of the lungs.

### Final Answer:
The correct answer is **upper part** (Option 1).

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