Based on different functional (R) groups the following amino acids are formed. Select the correct amino acid according to different functional groups.

Options

A. `R rarrH` (glycine)
B. `RrarrCH_3` (alanine)
C. `RrarrCH_2OH` (serine)
D. All the above

Answer

To solve the question regarding the correct amino acids based on different functional (R) groups, we will follow these steps:

### Step 1: Understand the General Structure of Amino Acids
Amino acids have a general structure that includes:
- An amino group (-NH2)
- A carboxyl group (-COOH)
- A hydrogen atom
- An R group (side chain) that varies among different amino acids.

### Step 2: Identify the Amino Acids Based on the R Groups
We will analyze the given R groups and identify the corresponding amino acids:

1. **R = H (Hydrogen)**:
- When the R group is simply hydrogen, the amino acid formed is **Glycine**.
- Glycine is the simplest amino acid.

2. **R = CH3 (Methyl Group)**:
- When the R group is a methyl group (CH3), the amino acid formed is **Alanine**.
- Alanine has a side chain that is a methyl group.

3. **R = CH2OH (Hydroxymethyl Group)**:
- When the R group is CH2OH, the amino acid formed is **Serine**.
- Serine contains a hydroxymethyl side chain.

### Step 3: Conclusion
Based on the analysis of the R groups:
- R = H corresponds to Glycine.
- R = CH3 corresponds to Alanine.
- R = CH2OH corresponds to Serine.

Since all the options provided are correct, the answer is **"All of the above."**

### Final Answer:
**All of the above.**

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