Which of the following activities, if not checked in time, may ultimately lead to the rise in sea level causing the flooding of low -lying coastal areas ?

Options

A. desalination
B. desertification
C. deforestation
D. desegregation

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which activity, if not controlled, could lead to rising sea levels and flooding in low-lying coastal areas.

2. **Identifying Key Activities**: The options likely include activities such as deforestation, industrial pollution, urbanization, and climate change.

3. **Analyzing Deforestation**:
- Deforestation refers to the removal of trees and vegetation.
- Trees play a crucial role in absorbing rainwater and facilitating its percolation into the soil.

4. **Impact of Deforestation on Water Cycle**:
- When trees are removed, the soil's ability to absorb water decreases.
- This leads to increased surface runoff, where rainwater does not get absorbed but instead flows directly into rivers and streams.

5. **Consequences of Increased Runoff**:
- The increased runoff can lead to higher water levels in rivers.
- When rivers overflow due to excess water, it can lead to flooding in nearby low-lying areas.

6. **Linking to Sea Level Rise**:
- Flooding in rivers can contribute to the overall rise in sea levels, especially if the water from the rivers eventually flows into the ocean.
- Additionally, activities like melting ice caps and glaciers due to climate change can also contribute to rising sea levels.

7. **Conclusion**: Among the activities mentioned, deforestation is a significant factor that can lead to increased runoff, flooding, and ultimately contribute to rising sea levels.

### Final Answer:
Deforestation is the activity that, if not checked in time, may ultimately lead to the rise in sea level causing the flooding of low-lying coastal areas.

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