Assertion: Genetic diversity of our crop plants must be conserved.
Reason: Genetic diversity is being or is likely to be used in the improvement of domesticated plants.

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "genetic diversity of our crop plants must be conserved." This means that it is essential to maintain a variety of genetic traits within crop species to ensure their health and productivity.

2. **Defining Genetic Diversity:**
- Genetic diversity refers to the range of different inherited traits within a species. It encompasses the variations in genes that contribute to the differences in characteristics among individuals of the same species.

3. **Importance of Genetic Diversity:**
- If genetic diversity is not conserved, it can lead to the development of pure line traits. Pure line traits mean that the same traits are passed down generation after generation, which can result in inbreeding depression.

4. **Understanding Inbreeding Depression:**
- Inbreeding depression occurs when closely related individuals breed, leading to a decrease in fitness and reproductive success. This happens because the lack of genetic variation can reduce the plant's ability to adapt to environmental changes or resist diseases.

5. **Linking Assertion to Reason:**
- The reason states that "genetic diversity is being or is likely to be used in the improvement of domesticated plants." This means that the variations in genetic traits can be utilized to enhance desirable characteristics in crops, such as yield and disease resistance.

6. **Examples of Genetic Improvement:**
- For instance, if a high-yielding plant is crossed with a disease-resistant plant, the offspring may inherit traits from both parents, resulting in a new variety that is both high-yielding and resistant to diseases.

7. **Conclusion:**
- Both the assertion and the reason are correct. The conservation of genetic diversity is crucial for the improvement of crop plants, as it allows for the development of new varieties that can better withstand challenges and improve food production.

**Final Answer:**
- The correct answer is that both the assertion and the reason are true, and the reason correctly explains the assertion.

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