Bacillus thuringiensis is a

Options

A. Biofertilizer
B. Biopesticide
C. Bioherbicide
D. Biofungicide

Answer

**Step-by-Step Solution:**

1. **Identify Bacillus thuringiensis**: Bacillus thuringiensis is a type of bacteria that is naturally occurring and found in soil.

2. **Understand its Function**: This bacterium is primarily used for natural insect control. It produces a specific type of protein crystal that is toxic to certain insects.

3. **Mechanism of Action**: The toxicity of Bacillus thuringiensis is due to the BT toxin it produces. When insects consume this toxin, it is activated in their highly alkaline gut, leading to the release of toxic crystals.

4. **Effect on Insects**: The BT toxin disrupts the digestive system of the insect, ultimately leading to its death through poisoning.

5. **Safety for Other Organisms**: Importantly, Bacillus thuringiensis is harmless to birds, fish, mammals, and humans, which makes it a safe option for pest control.

6. **Conclusion**: Based on its properties and effects, Bacillus thuringiensis is classified as a biopesticide.

7. **Final Answer**: Therefore, the correct option is that Bacillus thuringiensis is a **bio pesticide**.

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