Pyruvic acid is obtained by

Options

A. Oxidation of acetaldehyde cyanohydrin
B. Oxidation of acetone cyanohydrin
C. Oxidation of formaldehyde cyanohydrin
D. None of these

Explanation

To determine how pyruvic acid is obtained, we can analyze the possible reactions mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Structure of Pyruvic Acid**:
Pyruvic acid has the chemical formula \( C_3H_4O_3 \) and can be represented as \( CH_3COCOOH \). It consists of a methyl group (CH3), a carbonyl group (C=O), and a hydroxyl group (OH).

2. **Understand the Options Given**:
The options provided are:
- Oxidation of acetaldehyde cyanohydrin
- Oxidation of acetone cyanohydrin
- Oxidation of formaldehyde cyanohydrin
- None of these

3. **Evaluate Each Option**:
- **Oxidation of Acetaldehyde Cyanohydrin**:
Acetaldehyde (ethanal) has the structure \( CH_3CHO \). When it reacts with cyanide, it forms acetaldehyde cyanohydrin. Oxidizing this compound can lead to the formation of pyruvic acid.

- **Oxidation of Acetone Cyanohydrin**:
Acetone (propanone) has the structure \( CH_3COCH_3 \). The cyanohydrin of acetone does not lead to pyruvic acid upon oxidation.

- **Oxidation of Formaldehyde Cyanohydrin**:
Formaldehyde (methanal) has the structure \( HCHO \). The cyanohydrin of formaldehyde does not yield pyruvic acid upon oxidation.

- **None of These**:
This option suggests that none of the previous reactions lead to pyruvic acid.

4. **Conclusion**:
The correct answer is that pyruvic acid is obtained from the oxidation of acetaldehyde cyanohydrin.

### Final Answer:
Pyruvic acid is obtained by the oxidation of acetaldehyde cyanohydrin.

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