In Bt cotton a transgenic plant, Bt refers to….

Options

A. bold cotton
B. Bacillus thuringiensis
C. beta carotene
D. tumor inducing bacteria

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what "Bt" stands for in Bt cotton, which is a type of transgenic plant.

2. **Identifying the Options**: The options provided are:
- A) Bald cotton
- B) Bacillus thuringiensis
- C) Beta carotene
- D) Tumor-inducing bacteria

3. **Evaluating the Options**:
- **A) Bald cotton**: This option does not relate to any known scientific terminology or relevance in the context of Bt cotton.
- **B) Bacillus thuringiensis**: This is a well-known bacterium that produces proteins toxic to certain insects, making it a strong candidate.
- **C) Beta carotene**: This is a pigment found in plants and does not relate to the context of Bt cotton.
- **D) Tumor-inducing bacteria**: This refers to Agrobacterium tumefaciens, which is not related to the Bt cotton context.

4. **Selecting the Correct Answer**: The most relevant and scientifically accurate option is B) Bacillus thuringiensis. This bacterium is used in genetic engineering to create Bt cotton, which is resistant to certain pests.

5. **Conclusion**: Therefore, in Bt cotton, "Bt" refers to Bacillus thuringiensis.

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