Which of the following process is responsible for the formation of delta at a place where rivers meet the sea?

Options

A. Emulsification
B. Colloid formation
C. Coagulation
D. peptisation

Explanation

To solve the question of which process is responsible for the formation of a delta at a place where rivers meet the sea, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Delta Formation**:
- A delta is formed at the mouth of a river where it meets a body of water, such as an ocean or sea. This occurs due to the deposition of sediments carried by the river.

2. **Identifying the Processes**:
- The question provides four options: emulsification, colloid formation, coagulation, and peptization. We need to analyze each option to determine which one is relevant to delta formation.

3. **Analyzing Each Option**:
- **Emulsification**: This is the process of mixing two immiscible liquids, such as oil and water. It is not related to sediment deposition.
- **Colloid Formation**: This refers to the formation of a colloidal solution, which is not directly responsible for delta formation.
- **Coagulation**: This is the process where colloidal particles aggregate together, often due to the presence of electrolytes. In the context of a river meeting the sea, the seawater contains various electrolytes that cause the colloidal particles (like clay) in the river water to coagulate and settle, leading to sediment deposition.
- **Peptization**: This is the process of converting a coagulated mass back into a colloidal solution, which is not relevant to delta formation.

4. **Conclusion**:
- Based on the analysis, the correct process responsible for the formation of a delta at a place where rivers meet the sea is **coagulation**. The electrolytes in seawater cause the colloidal particles from the river to coagulate and settle, forming a delta.

### Final Answer:
The process responsible for the formation of a delta at a place where rivers meet the sea is **coagulation**.

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