Assertion :- According to Mendel, a dihybrid cross is the multiple
of two monohybrid crosses.
Reason :- When two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the
other pair of characters.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are trur but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is Flase.
D. If both Assertion & Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that according to Mendel, a dihybrid cross is the multiple of two monohybrid crosses. To understand this, we need to recall what a monohybrid cross is. A monohybrid cross involves the study of one trait at a time, while a dihybrid cross involves two traits. Therefore, when performing a dihybrid cross, we are essentially combining the outcomes of two separate monohybrid crosses.

2. **Understanding the Reason**: The reason provided states that when two pairs of traits are combined in a hybrid, the segregation of one pair of characters is independent of the other pair. This aligns with Mendel's Law of Independent Assortment, which states that alleles for different traits segregate independently during gamete formation. This means that the inheritance of one trait will not affect the inheritance of another trait.

3. **Evaluating the Truth of Both Statements**:
- The assertion is true because a dihybrid cross can be viewed as the combination of two monohybrid crosses.
- The reason is also true as it reflects Mendel's findings regarding the independent assortment of alleles.

4. **Determining the Relationship**: Although both the assertion and reason are true, the reason does not directly explain the assertion. The assertion speaks about the relationship between dihybrid and monohybrid crosses, while the reason discusses the independent segregation of traits, which is a broader principle.

5. **Conclusion**: Based on the evaluation, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

**Final Answer**: The correct option is B: Both assertion and reason are true, but reason is not the correct explanation of the assertion.

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