Assertion: `alpha`-amino acids exist as dipolar ions or zwitter ion.
Reason: `alpha`-amino acids are the building blocks of proteins.

Options

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the corret explanation of the assertion.
C. If assertion is true but reason is false.
D. If the assertion and the reason both are false.

Explanation

To solve the question regarding the assertion and reason provided, we need to analyze both statements carefully.

### Step 1: Understand the Assertion
The assertion states that `alpha`-amino acids exist as dipolar ions or zwitter ions.

- **Explanation**: `Alpha`-amino acids contain both an amino group (-NH2) and a carboxyl group (-COOH). In a neutral solution, the carboxyl group donates a proton (H+) and becomes negatively charged (-COO^-), while the amino group accepts a proton and becomes positively charged (-NH3^+). This results in a molecule that has both positive and negative charges, thus existing as a zwitterion (dipolar ion).

### Step 2: Understand the Reason
The reason states that `alpha`-amino acids are the building blocks of proteins.

- **Explanation**: This statement is true. `Alpha`-amino acids are indeed the monomers that combine to form proteins through peptide bonds. Each protein is made up of a specific sequence of these amino acids.

### Step 3: Analyze the Relationship
Now, we need to determine if the reason provided explains the assertion.

- **Analysis**: While both statements are true, the reason does not directly explain why `alpha`-amino acids exist as zwitter ions. The existence of zwitter ions is due to the structure of the amino acids and their ability to ionize in solution, not directly because they are building blocks of proteins.

### Conclusion
- **Assertion**: True
- **Reason**: True, but it does not explain the assertion.

Thus, the correct answer is that both the assertion and reason are correct, but the reason is not the correct explanation of the assertion.

### Final Answer
Both the assertion and reason are correct, but the reason is not the correct explanation of the assertion.

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