What causes pollution?

Options

A. Human activities
B. Trees
C. Both of these
D. None of these

Explanation

### Step-by-Step Text Solution:

1. **Understanding Pollution**: Pollution refers to the degradation of the environment, which can occur in various forms such as air pollution, water pollution, soil pollution, and noise pollution.

2. **Identifying Causes of Pollution**: The primary cause of pollution is human activities. These activities significantly impact the environment in several ways.

3. **Air Pollution**: Human activities such as the use of vehicles release harmful chemicals into the air. These chemicals often include poisonous gases that contribute to air pollution.

4. **Soil Pollution**: The establishment of factories by humans can lead to soil degradation. Factories often produce waste that contaminates the land, leading to soil pollution.

5. **Water Pollution**: Waste materials from factories are often dumped into water bodies. This practice harms aquatic life. For instance, arsenic from the paper industry can severely affect the health of aquatic organisms, leading to water pollution.

6. **Noise Pollution**: The sounds generated by vehicles and loudspeakers contribute to noise pollution, which is another form of environmental degradation caused by human activities.

7. **Conclusion**: In summary, human activities are the main cause of pollution across all types—air, soil, water, and noise. Other factors, such as trees, actually help reduce pollution rather than cause it.

### Final Answer:
The primary cause of pollution is human activities.

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