Weeds are the unwanted plants that grow along with the main crop in the field. These plants compete with the main crop for resources such as water, nutrients, and sunlight, and can significantly reduce the yield and quality of the crop. Weeds can also serve as hosts for pests and diseases, further impacting the health and productivity of the main crop.

Here is a detailed explanation of the answer:

Unwanted Plants in the Field:
- The plants that are not intentionally sown or cultivated by the farmer are considered unwanted plants.
- These plants can be native or introduced species and have the ability to grow and reproduce rapidly in the field.
- They usually have aggressive growth habits and can outcompete the main crop for resources.

Definition of Weeds:
- Weeds are defined as plants that are considered undesirable or troublesome in a particular situation, such as a cultivated field.
- They are often characterized by their ability to adapt to various environmental conditions and reproduce prolifically.
- Weeds can be annuals, biennials, or perennials, depending on their life cycle.

Impact of Weeds on Main Crops:
- Weeds compete with the main crop for resources such as water, nutrients, and sunlight.
- They can reduce the productivity and quality of the main crop by depriving it of essential resources.
- Weeds can also interfere with harvesting operations, making it difficult to efficiently harvest the main crop.

Control Measures for Weeds:
- Farmers employ various methods to control weeds and minimize their impact on the main crop.
- Cultural practices such as crop rotation, proper spacing, and timely sowing can help suppress weed growth.
- Mechanical methods like hand weeding, hoeing, and plowing can physically remove weeds from the field.
- Chemical control methods involve the use of herbicides or weedicides, which are chemicals specifically designed to kill or inhibit the growth of weeds.
- Integrated weed management strategies combine multiple control methods to effectively manage weed populations.

Conclusion:
Weeds are unwanted plants that grow along with the main crop in the field. They compete with the main crop for resources and can significantly reduce its yield and quality. Farmers employ various control measures to manage weed populations and minimize their impact on the main crop.

Correct Option is 'D'.. Already given...
Ans-) Weeds...
Explanation-) The waste plants that grow along with the crop in the field are called weeds. These are removed by ploughing the land before sowing the seeds...
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