Assertion. An amino acid in polypeptide chain is not altered due to change in third base of codon.
Reason. It is due to Wobble hypothesis.

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 explanations 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 an amino acid in a polypeptide chain is not altered due to a change in the third base of the codon. This is a reference to the redundancy in the genetic code, where multiple codons can code for the same amino acid.

2. **Understanding the Reason**: The reason provided is the Wobble hypothesis, which explains how the third base of a codon can vary without affecting the amino acid that is incorporated into the polypeptide chain. According to this hypothesis, the first two bases of the codon are more critical for determining the amino acid, while the third base can be less specific.

3. **Connecting Assertion and Reason**: The assertion is supported by the reason. The Wobble hypothesis explains why changes in the third base of a codon do not typically lead to changes in the amino acid sequence of proteins. This is because the tRNA can still recognize the codon and attach the correct amino acid even if the third base is different.

4. **Conclusion**: Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the statement is valid.

### Final Answer:
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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