The main aim of plant breeding is to:

Options

A. Control pollution
B. Keep soil fertile
C. Produce improved varieties
D. To maintain wild plants.

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Breeding**: Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. This involves selecting parent plants with specific traits and breeding them to create offspring with those desired traits.

2. **Main Objectives of Plant Breeding**:
- **Increase Crop Yield**: One of the primary goals is to enhance the productivity of crops, ensuring that more food can be produced from the same amount of land.
- **Improve Quality**: This includes enhancing the nutritional value, taste, and marketability of crops.
- **Disease Resistance**: Developing varieties that can withstand diseases and pests is crucial for sustainable agriculture.
- **Tolerance to Environmental Stresses**: Breeding plants that can survive in adverse conditions, such as drought or salinity, is essential for maintaining food security.

3. **Evaluating the Options**:
- **Control Pollution**: While important, this is not a direct aim of plant breeding.
- **Keep Soil Fertile**: Soil fertility is managed through various agricultural practices, not specifically through plant breeding.
- **Produce Improved Varieties**: This aligns with the main aim of plant breeding, as it focuses on developing new plant varieties with desirable traits.
- **Maintain Wild Plants**: Conservation of wild plants is important, but it is not the primary focus of plant breeding.

4. **Conclusion**: The main aim of plant breeding is to produce improved varieties of plants that have better yields, quality, and resistance to diseases and environmental stresses.

**Final Answer**: The main aim of plant breeding is to produce improved varieties.

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