Which of these agricultural practices must be carried out before sowing of seeds?

Options

A. seed selection
B. irrigation
C. harvesting
D. weeding

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for agricultural practices that must be carried out before sowing seeds. This means we need to identify the steps that occur prior to planting seeds in the soil.

2. **Identifying Agricultural Practices**: The practices mentioned in the transcript include:
- Seed Selection
- Irrigation
- Weeding
- Harvesting

3. **Analyzing Each Practice**:
- **Seed Selection**: This is the process of choosing the right seeds for planting. It involves checking the seeds by putting them in water to see which ones float (hollow and unhealthy) and which ones sink (healthy and suitable for germination). This is the first step before sowing seeds.
- **Irrigation**: This refers to watering the crops, which is done after the seeds have been sown, not before.
- **Weeding**: This involves removing unwanted plants that grow alongside the crops, which also occurs after sowing.
- **Harvesting**: This is the process of collecting mature crops, which is the last step in crop production.

4. **Conclusion**: Based on the analysis, the only agricultural practice that must be carried out before sowing seeds is **Seed Selection**.

### Final Answer:
The agricultural practice that must be carried out before sowing seeds is **Seed Selection**.

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