Which of the following is an essential amino acid ?

Options

A. Methionine
B. Tyrosine
C. Alanine
D. Glycine

Explanation

To determine which of the following is an essential amino acid, we first need to understand what essential amino acids are.

### Step 1: Define Essential Amino Acids
Essential amino acids are those that cannot be synthesized by the human body and must be obtained through diet. There are nine essential amino acids that humans need for proper health and growth.

### Step 2: List the Essential Amino Acids
The nine essential amino acids are:
1. Histidine
2. Isoleucine
3. Leucine
4. Lysine
5. Methionine
6. Phenylalanine
7. Threonine
8. Tryptophan
9. Valine

### Step 3: Identify the Options
If the question provides a list of amino acids, we need to compare each option with the list of essential amino acids mentioned above.

### Step 4: Select the Essential Amino Acid
From the options given, identify which one matches any of the nine essential amino acids listed.

### Conclusion
The amino acid that matches any of the essential amino acids from the list is the answer to the question.

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