Opposition to the construction of large dams is due to

Options

A. social reasons
B. economic reasons
C. environmental reasons
D. All of these

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why there is opposition to the construction of large dams. We need to consider various factors that contribute to this opposition.

2. **Identifying Reasons for Opposition**:
- **Social Reasons**: Large dam constructions often lead to the displacement of communities. People living in the vicinity of the dam may be forced to relocate, disrupting their lives and social structures.
- **Economic Reasons**: The construction of large dams can result in loss of agricultural land for local farmers, leading to economic hardships. Often, displaced individuals do not receive adequate compensation for their lost land and livelihoods.
- **Environmental Reasons**: Large dams can have significant environmental impacts, such as altering ecosystems, causing flooding, and affecting wildlife habitats. These environmental changes can lead to long-term ecological damage.

3. **Evaluating the Options**:
- Option 1: Social reasons - True, as displacement occurs.
- Option 2: Economic reasons - True, as people lose their land and livelihoods.
- Option 3: Environmental reasons - True, as there are ecological impacts.
- Option 4: All of these - This option encompasses all the aforementioned reasons.

4. **Conclusion**: Since all three reasons (social, economic, and environmental) contribute to the opposition against large dam constructions, the correct answer is option 4: all of these.

### Final Answer:
The opposition to the construction of large dams is due to social, economic, and environmental reasons, making the correct option "all of these."

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