Which of the following is not used for crop improvement ?

Options

A. Siltation
B. ntroduction
C. Hybridization
D. Mutations

Answer

**Step-by-Step Solution:**

1. **Understanding Crop Improvement Methods**:
- Crop improvement involves various techniques aimed at enhancing the quality and yield of crops. Common methods include introduction of new varieties, hybridization, and mutation.

2. **Analyzing the Options**:
- The question provides four options:
- A. Siltation
- B. Introduction
- C. Hybridization
- D. Mutation

3. **Evaluating Each Option**:
- **Option A: Siltation**: This term refers to the accumulation of silt in water bodies, which is a form of water pollution. It does not contribute to improving crops.
- **Option B: Introduction**: This method involves bringing new plant varieties into cultivation, which is a recognized technique for crop improvement.
- **Option C: Hybridization**: This is the process of crossing different plant varieties to produce hybrids with desirable traits, widely used in crop improvement.
- **Option D: Mutation**: This involves inducing changes in the genetic material of plants to create new traits, also a method used for crop improvement.

4. **Identifying the Correct Answer**:
- Since Siltation is related to water pollution and does not contribute to crop improvement, it is the correct answer to the question.

5. **Conclusion**:
- The method that is not used for crop improvement is **A. Siltation**.

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