It is said that the Taj Mahal may be destroyed due to :

Options

A. Flood in Yamuna river
B. Air pollutants released from oil refinery of Mathura
C. Decomposition of marble as a result of high temperature
D. All the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the potential causes for the destruction of the Taj Mahal.

2. **Analyzing the Options**:
- **Option A**: Flooding of the Yamuna River.
- **Option B**: Air pollutants released from the oil refinery of Mathura.
- **Option C**: Decomposition of marble due to high temperature.
- **Option D**: All of the above.

3. **Evaluating Each Option**:
- **Option A (Flooding of the Yamuna River)**: While flooding can cause damage, it is not the primary concern for the Taj Mahal's deterioration.
- **Option B (Air pollutants from Mathura)**: This is a significant concern. The oil refinery releases harmful air pollutants like Nitrogen Dioxide and Sulphur Dioxide, which can lead to acid rain.
- **Option C (Decomposition due to high temperature)**: High temperatures can affect materials, but the primary issue for the Taj Mahal is not temperature alone but the chemical reactions caused by pollutants.
- **Option D (All of the above)**: Since Options A and C are not the main causes, this option cannot be correct.

4. **Identifying the Correct Answer**: The most significant threat to the Taj Mahal comes from air pollutants released from the oil refinery in Mathura, which leads to acid rain that reacts with the marble.

5. **Conclusion**: The correct answer is **Option B**: Air pollutants released from the oil refinery of Mathura.