Assertion : 'Bt' toxin gene has been cloned from bacteria and expressed in plants to provide resistance from insect without the need of insecticides.
Reason: 'Bt' toxin is produced from bacterium Bacillus thuringiensis.

Options

A. If both Assertion and Reason are true and Reason is correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that the 'Bt' toxin gene has been cloned from bacteria and expressed in plants to provide resistance against insects without the need for insecticides. This is true because genetically modified plants, such as Bt cotton, have been developed to produce the Bt toxin, which is effective against certain pests.

2. **Understanding the Reason**: The reason provided is that 'Bt' toxin is produced from the bacterium Bacillus thuringiensis. This is also true, as Bacillus thuringiensis is known for producing proteins (Bt toxins) that are toxic to specific insects.

3. **Analyzing the Relationship**: While both the assertion and the reason are true, we need to determine if the reason correctly explains the assertion. The assertion discusses the application of the Bt toxin gene in plants to provide insect resistance, while the reason simply states the source of the toxin.

4. **Conclusion**: Since the reason does not explain how the Bt toxin provides resistance (it does not mention the mechanism of action of the toxin in the insect's gut), we conclude that the assertion is true, the reason is true, but the reason is not the correct explanation for the assertion.

5. **Final Answer**: Therefore, the correct option is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

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