When glycolic acid is subjected to reduction with `HI`, the product formed is :

Options

A. Acetic acid
B. Formic acid
C. Iodoacetic acid
D. None of the above

Explanation

To solve the question regarding the reduction of glycolic acid with hydrogen iodide (HI), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Glycolic Acid**:
- Glycolic acid has the chemical formula HOOCCH2OH. It consists of a carboxylic acid group (-COOH) and a hydroxyl group (-OH) attached to a carbon atom.

2. **Understand the Role of HI in Reduction**:
- Hydrogen iodide (HI) is a strong reducing agent. In this context, it will reduce the hydroxyl group (-OH) of glycolic acid.

3. **Reduction of the Hydroxyl Group**:
- The hydroxyl group (-OH) on the glycolic acid structure (CH2OH) will be reduced to a methyl group (-CH3). This means that the -OH group will lose its oxygen and hydrogen, effectively converting the carbon it is attached to from -CH2OH to -CH3.

4. **Formation of the Product**:
- After the reduction of the hydroxyl group, the remaining structure will be the carboxylic acid group (-COOH) attached to the newly formed methyl group (-CH3). Therefore, the product formed is HOOCCH3, which is the structure of acetic acid.

5. **Conclusion**:
- Thus, when glycolic acid is subjected to reduction with HI, the product formed is acetic acid (CH3COOH).

### Final Answer:
The product formed when glycolic acid is subjected to reduction with HI is **Acetic Acid**.

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