Assertion (A): Polygenic inheritance gives rise to varied skin tones in `F_(2)` generation.
Reason ( R): Phenotype reflects the contribution of each allele, is influenced by the environment in case of polygenic inheritance.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and Rare true but is not the correct explanation of A
C. A is true but R is false
D. A is false but R is true

Explanation

To solve the question, we need to analyze both the Assertion (A) and Reason (R) provided.

**Step 1: Understand the Assertion (A)**
- The assertion states that "Polygenic inheritance gives rise to varied skin tones in F2 generation."
- Polygenic inheritance refers to the inheritance of traits that are controlled by multiple genes. In the case of human skin color, it is influenced by several genes, resulting in a wide range of skin tones.
- In the F2 generation, when two heterozygous parents are crossed, the offspring can exhibit a variety of phenotypes due to the combination of alleles inherited from both parents. This supports the assertion that polygenic inheritance leads to varied skin tones.

**Step 2: Understand the Reason (R)**
- The reason states that "Phenotype reflects the contribution of each allele, is influenced by the environment in case of polygenic inheritance."
- The phenotype is the observable characteristics of an organism, which in this case includes skin color. In polygenic inheritance, the phenotype is determined by the cumulative effect of multiple alleles.
- Additionally, environmental factors can also influence the expression of these traits. For example, exposure to sunlight can darken skin tone, which further supports the reason provided.

**Step 3: Analyze the relationship between A and R**
- Both the assertion and reason are correct. The assertion accurately describes the outcome of polygenic inheritance in terms of varied skin tones, and the reason correctly explains how phenotypes are determined by multiple alleles and environmental influences.
- Furthermore, the reason serves as a valid explanation for the assertion, as it clarifies how the contributions of multiple alleles lead to the observed variation in skin tones.

**Conclusion**
- Both the assertion (A) and reason (R) are correct, and the reason is the correct explanation of the assertion.

**Final Answer:**
Both Assertion (A) and Reason (R) are correct, and R is the correct explanation of A.

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