Deforestation generally decreases:-

Options

A. Rain fall
B. Soil erosion
C. Drought
D. Global warming.

Answer

### Step-by-Step Solution:

1. **Understanding Deforestation**:
- Deforestation refers to the large-scale removal of trees from forested areas, which can lead to significant environmental changes.

2. **Impact on Rainfall**:
- Trees play a crucial role in the water cycle through a process called transpiration, where they release water vapor into the atmosphere. This process contributes to cloud formation and ultimately rainfall.
- When trees are removed, the amount of transpiration decreases, leading to a reduction in rainfall.

3. **Analyzing Other Options**:
- **Soil Erosion**: Deforestation can lead to increased soil erosion because tree roots help to anchor the soil. Without trees, the soil becomes more susceptible to being washed away by rain.
- **Drought**: With reduced rainfall, areas may experience drought conditions more frequently.
- **Global Warming**: Deforestation contributes to global warming as trees absorb carbon dioxide. Fewer trees mean more carbon dioxide in the atmosphere, which contributes to the greenhouse effect.

4. **Conclusion**:
- From the analysis, it is clear that deforestation primarily decreases rainfall while increasing soil erosion, drought, and global warming. Therefore, the correct answer to the question is that deforestation generally decreases **rainfall**.

### Final Answer:
Deforestation generally decreases **rainfall**.

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