The aromatic amino acid(s) is (are) - .

Options

A. Typrosine
B. Phenylalanine
C. Tryptophan
D. All

Answer

To determine the aromatic amino acids, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Aromatic Amino Acids**: Aromatic amino acids are those that contain an aromatic ring in their side chain (R group). This characteristic is essential for identifying them.

2. **Identify Common Aromatic Amino Acids**: The three primary aromatic amino acids are:
- **Phenylalanine**: Contains a phenyl group (a benzene ring) in its side chain.
- **Tyrosine**: Similar to phenylalanine but has a hydroxyl (-OH) group attached to the benzene ring.
- **Tryptophan**: Contains an indole ring, which is a fused double-ring structure that includes a benzene ring.

3. **List the Options**: If the question provides options, check if they include phenylalanine, tyrosine, or tryptophan.

4. **Select the Correct Answer**: If all three amino acids (phenylalanine, tyrosine, and tryptophan) are included in the options, then the correct answer is that all of them are aromatic amino acids.

5. **Conclusion**: Based on the identification of the amino acids and their structures, we conclude that phenylalanine, tyrosine, and tryptophan are the aromatic amino acids.

### Final Answer:
The aromatic amino acids are phenylalanine, tyrosine, and tryptophan.

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