Amino acids are :

Options

A. acidic
B. basic
C. amphoteric
D. neutral

Answer

**Step-by-Step Solution:**

1. **Understanding Amino Acids**: Amino acids are organic compounds that serve as the building blocks of proteins. They contain both an amino group (-NH2) and a carboxyl group (-COOH) attached to a central carbon atom.

2. **General Structure of Amino Acids**: The general structure of an amino acid can be represented as:
\[ \text{H}_2\text{N}-\text{C}(\text{R})-\text{COOH} \]
Here, 'R' represents the side chain that varies among different amino acids.

3. **Properties of Amino Acids**: Due to the presence of both the amino group and the carboxyl group, amino acids can react with acids and bases. This dual reactivity is a key characteristic of amino acids.

4. **Amphoteric Nature**: The ability of a substance to react with both acids and bases is referred to as amphoteric behavior. Since amino acids can donate a proton (H+) from the carboxyl group to a base and accept a proton (H+) at the amino group from an acid, they are classified as amphoteric.

5. **Conclusion**: Therefore, the correct statement about amino acids is that they are amphoteric in nature, meaning they can react with both acids and bases.

**Final Answer**: Amino acids are amphoteric in nature.

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