Assertion :- Simply looking at the phenotype is not possible to known the genotypic composition.
Reason :- Mendel performed reciprocoal crossed to know the genotype of dominant organism.

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 simply looking at the phenotype of an organism does not allow us to determine its genotypic composition. This is true because phenotypes can be similar for different genotypes, especially when dealing with dominant traits. For example, both homozygous dominant (AA) and heterozygous (Aa) individuals can exhibit the same dominant phenotype.

2. **Understanding the Reason**: The reason provided is that Mendel performed reciprocal crosses to determine the genotype of dominant organisms. A reciprocal cross involves switching the roles of the parents in a genetic cross to observe the inheritance patterns. This method helps in understanding how traits are passed on but is not specifically aimed at determining the genotype of a dominant organism.

3. **Evaluating the Assertion and Reason**: The assertion is true because phenotypic observation alone cannot reveal the underlying genotype. However, the reason is misleading because while Mendel did use reciprocal crosses, it was primarily to study inheritance patterns rather than to determine the genotype of dominant organisms directly.

4. **Conclusion**: Since the assertion is true and the reason is false, the correct option is that the assertion is true but the reason is false.

**Final Answer**: The assertion is true, but the reason is false.

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