Bt cotton is not

Options

A. a genetically modified (GM) plant.
B. insect resistant
C. a bacterial gene expressing system.
D. resistant to all pesticides.

Explanation

To answer the question "Bt cotton is not," we need to analyze the characteristics of Bt cotton and identify what it does not possess.

### Step-by-Step Solution:

1. **Understanding Bt Cotton**:
- Bt cotton is a genetically modified organism (GMO) that has been engineered to express a protein from the bacterium *Bacillus thuringiensis* (Bt). This protein is toxic to certain insects, making the plant resistant to pest attacks.

2. **Identifying Characteristics of Bt Cotton**:
- **Genetically Modified**: Bt cotton is indeed a genetically modified plant.
- **Insect Resistant**: It is designed to be resistant to specific insects, particularly those that are harmful to cotton crops.
- **Bacterial Gene Expression**: It contains genes from the soil bacterium *Bacillus thuringiensis*, which allows it to produce the insecticidal protein.

3. **Evaluating the Options**:
- The question asks what Bt cotton is not.
- One of the options states that "Bt cotton is resistant to all pesticides." This is incorrect because Bt cotton is specifically engineered to be resistant to certain pests, but it is not resistant to all pesticides. In fact, it can still be affected by herbicides and other chemical treatments.

4. **Conclusion**:
- Therefore, the correct answer to the question "Bt cotton is not" would be that it is **not resistant to all pesticides**.

### Final Answer:
Bt cotton is not resistant to all pesticides.

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