Among the following, the essential amino acid is :

Options

A. Valine
B. Alanine
C. Serine
D. Aspartic acid

Answer

To determine which of the given amino acids is essential, we need to understand the definition of essential amino acids. Essential amino acids are those that cannot be synthesized by the body and must be obtained through the diet.

### Step-by-Step Solution:

1. **Identify the Amino Acids**: The options provided are:
- Option A: Valine
- Option B: Alanine
- Option C: Serine
- Option D: Aspartic Acid

2. **List Essential Amino Acids**: Essential amino acids include:
- Valine
- Leucine
- Isoleucine
- Methionine
- Phenylalanine
- Tryptophan
- Threonine
- Lysine
- Histidine

3. **Evaluate Each Option**:
- **Option A: Valine** - This is an essential amino acid.
- **Option B: Alanine** - This is a non-essential amino acid.
- **Option C: Serine** - This is a non-essential amino acid.
- **Option D: Aspartic Acid** - This is a non-essential amino acid.

4. **Conclusion**: Since Valine is the only amino acid listed that is essential, the correct answer is:
- **Option A: Valine**

### Final Answer:
The essential amino acid among the options is **Option A: Valine**.

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