Cotton dust is an important pollution in

Options

A. Delhi
B. Ahmedabad
C. madras
D. calcutta

Answer

### Step-by-Step Solution:

1. **Identify the Context**: The question asks about cotton dust as an important pollutant in specific cities. We need to determine where cotton dust is a significant environmental concern.

2. **List the Cities Mentioned**: The cities mentioned in the question are Delhi, Ahmedabad, Madras, and Calcutta. We need to analyze which of these cities is most associated with cotton dust pollution.

3. **Understand Cotton Dust**: Cotton dust is defined as the dust present in the air during the handling or processing of cotton. It can contain various harmful components, including cotton fibers, bacteria, fungi, soil particles, and other contaminants.

4. **Identify the Source of Cotton Dust**: Cotton dust accumulates during the growing, harvesting, and processing of cotton. This means that areas with significant cotton production and processing will likely have higher levels of cotton dust pollution.

5. **Determine the Largest Cotton Producing State**: According to the information provided, Gujarat is identified as the largest cotton-producing state in India. This suggests that cities in Gujarat may experience more cotton dust pollution.

6. **Conclude with the Correct City**: Among the cities listed, Ahmedabad is located in Gujarat, making it the most relevant city in the context of cotton dust pollution. Therefore, the correct answer is Ahmedabad.

### Final Answer:
Cotton dust is an important pollutant in Ahmedabad.

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