Amino acids are:

Options

A. Acidic
B. Basic
C. Amphoteric
D. Neutral

Explanation

### Step-by-Step Solution

1. **Understanding the Structure of Amino Acids**:
- Amino acids have a general structure that includes a central carbon atom (C) bonded to four different groups: an amino group (-NH2), a carboxylic acid group (-COOH), a hydrogen atom (H), and a variable side chain (R group) which differs among different amino acids.

2. **Identifying Functional Groups**:
- The amino group (-NH2) can accept protons (H+) due to the presence of a lone pair of electrons on the nitrogen atom. This characteristic indicates that the amino group can act as a base.

3. **Analyzing the Carboxylic Acid Group**:
- The carboxylic acid group (-COOH) can donate protons (H+) because it contains a hydroxyl group (-OH) that can release H+. This indicates that the carboxylic acid group can act as an acid.

4. **Determining the Nature of Amino Acids**:
- Since amino acids contain both an amino group (which can act as a base) and a carboxylic acid group (which can act as an acid), they exhibit both acidic and basic properties.

5. **Conclusion**:
- Compounds that can act as both acids and bases are classified as amphoteric. Therefore, amino acids are amphoteric in nature.

### Final Answer:
Amino acids are amphoteric.

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