Flooding of the field controls:

Options

A. Fungi
B. Bacteria
C. Viruse
D. Nematodes

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which type of organism is controlled by flooding of the field. The options provided are fungi, bacteria, viruses, and nematodes.

2. **Identifying the Impact of Flooding**: Flooding of fields is a method used in agriculture to manage pests and diseases. It can create an environment that is unfavorable for certain pests.

3. **Focus on Nematodes**: Among the options, nematodes are known to be affected by flooding. Nematodes, particularly root-knot nematodes, can enter plant roots as larvae and cause significant damage by forming galls or knots on the roots.

4. **Mechanism of Control**: When fields are flooded, the excess water can drown the nematodes or disrupt their life cycle. This can lead to a reduction in their population, thereby protecting the plants from damage.

5. **Conclusion**: Based on the understanding that flooding effectively reduces the number of nematodes that can harm plants, the correct answer to the question is **nematodes**.

**Final Answer**: Flooding of the field controls nematodes.

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