Assertion :- According to Mendel, a dilhyorid 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 Text Solution:

1. **Understanding the Assertion**:
- The assertion states that "According to Mendel, a dihybrid cross is the multiple of two monohybrid crosses."
- A dihybrid cross involves two traits, and it can be understood as the combination of two separate monohybrid crosses, each involving one trait.

2. **Understanding the Reason**:
- The reason states that "When two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair of characters."
- This refers to Mendel's Law of Independent Assortment, which posits that alleles for different traits segregate independently during gamete formation.

3. **Connecting Assertion and Reason**:
- The assertion is correct because a dihybrid cross can indeed be viewed as the product of two monohybrid crosses.
- The reason is also correct as it explains the principle behind the assertion, highlighting that the segregation of traits occurs independently.

4. **Conclusion**:
- Both the assertion and the reason are true. The reason correctly explains the assertion.
- Therefore, the correct answer is: "Assertion and reason are both true, and the reason is the correct explanation of the assertion."