Describe the threat to the beauty of the Taj Mahal.

Explanation

### Step-by-Step Solution:

1. **Introduction to the Taj Mahal**: The Taj Mahal is a world-renowned monument located in Agra, India, known for its stunning white marble architecture and intricate designs.

2. **Threats to the Taj Mahal's Beauty**: The beauty of the Taj Mahal is threatened primarily by environmental factors, particularly air pollution and acid rain.

3. **Acid Rain**: Acid rain occurs when pollutants in the atmosphere, such as sulfur dioxide and nitrogen oxides, combine with water vapor to form acidic compounds. When this acid rain falls on the Taj Mahal, it reacts with the marble.

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