Which of the following is not a cause of natural pollution ?

Options

A. Volcanic eruption
B. UV radiation
C. Forest fire
D. Mercury

Explanation

To determine which of the following options is not a cause of natural pollution, we will analyze each option based on their origins and whether they are natural or anthropogenic (human-made).

### Step-by-Step Solution:

1. **Understand Natural Pollution**:
- Natural pollution refers to pollutants that originate from natural sources or processes. Examples include volcanic eruptions, forest fires, and emissions from plants and animals.

2. **Analyze Each Option**:
- **Volcanic Eruption**: This is a natural phenomenon where magma from beneath the Earth’s crust erupts, releasing gases and ash into the atmosphere. This is a cause of natural pollution.
- **UV Radiation**: Ultraviolet radiation is a natural part of sunlight. While it can cause harm to living organisms, it is not a pollutant in the traditional sense. It does not originate from a human-made source.
- **Forest Fire**: Forest fires can occur naturally due to lightning strikes or other natural causes. They release carbon dioxide and other pollutants into the atmosphere, making them a cause of natural pollution.
- **Mercury**: Mercury is a heavy metal that can cause pollution, but it is primarily released into the environment through human activities such as mining and industrial processes. It is not a natural pollutant.

3. **Identify the Correct Answer**:
- Among the options, **mercury** is the only one that is not a cause of natural pollution as it is primarily associated with human activities.

### Conclusion:
The correct answer is **mercury** (Option 4) as it is not a cause of natural pollution.

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