Assertion: A gene from bacillus thuringiensis is incorporated in plant genome to increases yield.
Reason : it is Bt toxin producing gene which kills larvae of insects.

Options

A. both are true with reason being correct explanation
B. both are true but reason is not correct explanation
C. assertion is true but reason is wrong
D. both are wrong

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that a gene from *Bacillus thuringiensis* (Bt) is incorporated into the plant genome to increase yield. This implies that genetic engineering is used to enhance plant productivity.

2. **Understanding the Reason**:
- The reason given is that the gene produces Bt toxin, which is effective in killing the larvae of various insects. This suggests that the incorporation of this gene helps the plant defend itself against insect pests.

3. **Linking Assertion and Reason**:
- The assertion and reason are connected. The incorporation of the Bt gene into the plant genome allows the plant to produce Bt toxin, which in turn protects the plant from insect damage. This protection leads to healthier plants that can yield more produce.

4. **Conclusion**:
- Since both the assertion and the reason are true, and the reason correctly explains the assertion, we can conclude that both statements are valid. Therefore, the correct option is that both are true, and the reason is the correct explanation for the assertion.

### Final Answer:
- Both the assertion and the reason are true, with the reason being the correct explanation for the assertion. The answer is option number one.

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