Consider the following statements.
I) Bt toxin gene has been cloned from the bacteria.
II) Genetic engineering works only on animals and has not yet been successfully used on plants.
III) Strains of Bacillus thuringiensis are used in producing bioinsecticidal plants.
Which of the statements given above are correct?

Options

A. I & II
B. I & III
C. II & III
D. I, II & III

Answer

To solve the question, we need to evaluate each of the three statements regarding biotechnology, specifically focusing on the Bt toxin gene and its applications.

### Step-by-Step Solution:

1. **Evaluate Statement I**: "Bt toxin gene has been cloned from the bacteria."
- The Bt toxin gene, known as the cry gene, has indeed been cloned from the bacterium Bacillus thuringiensis. This gene is responsible for producing a protein that is toxic to certain insects. Therefore, this statement is **correct**.

2. **Evaluate Statement II**: "Genetic engineering works only on animals and has not yet been successfully used on plants."
- This statement is **incorrect**. Genetic engineering has been successfully applied to both animals and plants. For example, Bt cotton and Bt potato are genetically engineered plants that express the Bt toxin gene, making them resistant to pests. Thus, this statement is **false**.

3. **Evaluate Statement III**: "Strains of Bacillus thuringiensis are used in producing bioinsecticidal plants."
- This statement is **correct**. The strains of Bacillus thuringiensis are utilized in the development of bioinsecticidal plants. When the Bt toxin gene is expressed in plants, these plants produce the toxin that protects them from insect pests, making them bioinsecticidal. Therefore, this statement is **true**.

### Conclusion:
Based on the evaluations:
- Statement I is correct.
- Statement II is incorrect.
- Statement III is correct.

Thus, the correct statements are I and III.

### Final Answer:
The correct statements are I and III.

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