Bt brinjal an example of transgenic crops. In this Bt refers to

Options

A. Bacillus tuberculosis
B. Biotechonlogy
C. `beta`-carotene
D. Bacillus thuringiensis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what "Bt" in Bt brinjal refers to. It's important to identify the correct term that "Bt" stands for in the context of transgenic crops.

2. **Identifying Options**: The options provided are:
- A) Bacillus tuberculosis
- B) Biotechnology
- C) Beta carotene
- D) Bacillus thuringiensis

3. **Analyzing Each Option**:
- **A) Bacillus tuberculosis**: This is a bacterium that causes tuberculosis in humans and is not related to brinjal.
- **B) Biotechnology**: While biotechnology is the field involved in creating transgenic crops, it does not specifically define "Bt".
- **C) Beta carotene**: This is a pigment found in plants, but it is not what "Bt" refers to in the context of Bt brinjal.
- **D) Bacillus thuringiensis**: This is a bacterium known for its insecticidal properties. It produces a protein that is toxic to certain pests, making it relevant to the development of pest-resistant crops.

4. **Conclusion**: Since Bt brinjal is genetically modified to include a gene from Bacillus thuringiensis, the correct answer is D) Bacillus thuringiensis.

5. **Final Answer**: Bt in Bt brinjal refers to Bacillus thuringiensis.

---