Bagging is done to
(a) Achieve desired pollination
(b) Prevent contamination from unwanted pollen
(c) Avoid self pollination
(d) Avoid cross pollination

Options

A. Achieve desired pollination
B. Prevent contamination from unwanted pollen
C. Aviod self pollination
D. Avoid cross pollination

Answer

To solve the question regarding the purpose of bagging in plant breeding, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Process of Bagging**:
- Bagging refers to covering flowers with a protective bag, usually made of butter paper or similar material, to prevent unwanted interactions during the pollination process.

2. **Identify the Context of Bagging**:
- Bagging is primarily used in hybridization processes, especially with emasculated flowers. Emasculated flowers are those from which the stamens (anthers) have been removed to prevent self-pollination.

3. **Analyze Each Option**:
- **Option (a)**: Achieve desired pollination - This is incorrect because bagging is not about achieving pollination; it is about controlling it.
- **Option (b)**: Prevent contamination from unwanted pollen - This is correct. Bagging prevents any unwanted pollen from contaminating the emasculated flower.
- **Option (c)**: Avoid self-pollination - This is also incorrect because emasculation already prevents self-pollination.
- **Option (d)**: Avoid cross-pollination - This is incorrect as well because bagging is done to control the type of pollination, not to avoid it entirely.

4. **Conclusion**:
- The primary purpose of bagging is to **prevent contamination from unwanted pollen** (Option b).

### Final Answer:
(b) Prevent contamination from unwanted pollen.

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