Which of the following can be controlled by using biopesticides?

Options

A. Insects
B. Diseases
C. Weeds
D. All of these

Answer

### Step-by-Step Solution:

1. **Understanding Biopesticides**: Biopesticides are natural pesticides derived from living organisms. They are used to control pests, pathogens, and weeds in agriculture.

2. **Types of Organisms Controlled**: Biopesticides can target various organisms:
- **Insects**: They can control insect pests that damage crops.
- **Pathogens**: They can help manage diseases caused by bacteria, fungi, and viruses.
- **Weeds**: They can also be effective against unwanted plant growth.

3. **Advantages of Biopesticides**:
- **Biodegradability**: Unlike synthetic pesticides, biopesticides are biodegradable, meaning they break down naturally and do not persist in the environment.
- **Long-term Effects**: They tend to have long-lasting effects on pest control without the harmful side effects associated with chemical pesticides.

4. **Conclusion**: Given that biopesticides can control insects, diseases, and weeds, the correct answer to the question is "all of these".

5. **Example**: An example of a biopesticide is **Bacillus thuringiensis**, a bacterium that produces a toxin harmful to certain insects, making it a widely used biopesticide in agriculture.

### Final Answer: All of these (insects, diseases, and weeds) can be controlled by using biopesticides.

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