The bacterium Bacillus thuringiensis is widely used in contemporary biology as a/an

Options

A. indicator of water pollution
B. insecticide
C. agent for production of dairy products
D. source of industrial enzyme

Answer

**Step-by-Step Solution:**

1. **Identify the Bacterium**: The question asks about the bacterium Bacillus thuringiensis (Bt). It is important to recognize what this bacterium is known for in biotechnology.

2. **Understand the Role of Bacillus thuringiensis**: Bacillus thuringiensis is a bacterium that produces a protein toxic to certain insects. This property is utilized in agriculture to protect crops from pest damage.

3. **Application in Biotechnology**: The gene responsible for the insecticidal properties of Bacillus thuringiensis has been incorporated into various crops, making them resistant to pests. This is commonly seen in genetically modified organisms (GMOs) such as Bt cotton.

4. **Conclusion**: Therefore, Bacillus thuringiensis is widely used in contemporary biology as a biological pesticide or insecticide, specifically in the development of pest-resistant crops.

**Final Answer**: Bacillus thuringiensis is widely used in contemporary biology as a biological pesticide.

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