Yellowing of marble of the Taj Mahal is caused by:

Options

A. Smog
B. Soot
C. Iron
D. Rain

Answer

**Step-by-Step Solution:**

1. **Identify the Problem:**
The question asks about the cause of the yellowing of the marble of the Taj Mahal.

2. **Research the Cause:**
The yellowing of the marble is primarily attributed to environmental pollution. In particular, emissions from nearby industrial activities can lead to this discoloration.

3. **Specific Source:**
The Mathura Oil Refinery is a significant contributor to this problem. It releases various pollutants into the atmosphere.

4. **Understand the Pollutants:**
The pollutants emitted include suspended particulate matter, particularly soot particles. These particles can settle on the surface of the marble, leading to its yellowing over time.

5. **Conclusion:**
Therefore, the yellowing of the marble of the Taj Mahal is caused by the emissions from the Mathura Oil Refinery, which includes soot and other particulate matter.

**Final Answer:**
The yellowing of the marble of the Taj Mahal is caused by the emissions from the Mathura Oil Refinery, which releases suspended particulate matter such as soot particles.

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