The carboxylic acid undergoing decarboxylation most readily is/are

Options

A.
B.
C.
D. both (A) and (B)

Answer

To determine which carboxylic acid undergoes decarboxylation most readily, we need to analyze the structure of the acids and their ability to lose carbon dioxide (CO2).

### Step-by-Step Solution:

1. **Understanding Decarboxylation**:
- Decarboxylation is the process where a carboxylic acid loses a carbon dioxide molecule (CO2). This process is often facilitated by the presence of certain structural features in the acid.

2. **Identifying Beta-Keto Acids**:
- Beta-keto acids are known to undergo decarboxylation readily. A beta-keto acid has a carbonyl group (C=O) adjacent to the carboxylic acid group (-COOH). The presence of the carbonyl group stabilizes the transition state during the decarboxylation process.

3. **Analyzing Given Options**:
- Let's consider the options provided in the question:
- **Option A**: Contains a carboxylic acid with a carbonyl group adjacent to it.
- **Option B**: Also contains a beta-keto structure.
- **Option C**: Does not have the necessary structure for rapid decarboxylation.
- **Option D**: States that both A and B are correct.

4. **Mechanism of Decarboxylation**:
- In the case of beta-keto acids, the lone pairs on the oxygen of the carboxylic acid can participate in the reaction. The hydrogen from the -COOH group can be abstracted, leading to the formation of a double bond and the release of CO2.

5. **Conclusion**:
- Since both options A and B contain beta-keto acid structures, they will undergo decarboxylation readily. Therefore, the correct answer is that both A and B will undergo decarboxylation most readily.

### Final Answer:
Both A and B will undergo decarboxylation most readily.