Assertion. Hybrid seeds must be produced every year to obtain maximum advantage of heterosis.
Reason. Heterosis is lost by inbreeding

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that hybrid seeds must be produced every year to obtain the maximum advantage of heterosis.
- Heterosis, or hybrid vigor, refers to the phenomenon where the F1 generation (offspring from a cross between two different parents) exhibits superior qualities compared to both parents.

2. **Analyzing the Reason**:
- The reason given is that heterosis is lost by inbreeding.
- Inbreeding involves mating between closely related individuals, which can lead to a decrease in genetic diversity and the potential loss of heterosis, as it increases homozygosity (the presence of identical alleles for a trait).

3. **Connecting Assertion and Reason**:
- The assertion is correct because hybrid seeds do need to be produced annually to maintain the benefits of heterosis. If hybrid seeds are not produced every year, the alleles in the hybrid seeds can segregate, leading to a loss of the advantageous traits associated with heterosis.
- The reason is also correct because inbreeding can indeed lead to a loss of heterosis due to increased homozygosity. When inbreeding occurs, the genetic diversity is reduced, which can diminish the advantages seen in hybrid vigor.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct option is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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