Which is the most suitable reagent for the following conversion ?
`CH_(3)-CH=CH-CH_(2)-overset(O)overset(||)(C)-CH_(3)to`
`CH_(3)-CH=CH-CH_(2)-overset(O)overset(||)(C)-OH`

Options

A. Tollen's reagent
B. Benzoyl peroxide
C. `I_(2)" and "NaOH` solution
D. `Sn" and "NaOH` solution

Explanation

To determine the most suitable reagent for the conversion of the compound \( CH_3-CH=CH-CH_2-CO-CH_3 \) to \( CH_3-CH=CH-CH_2-COOH \), we need to analyze the transformation that is taking place. The goal is to convert the ketone functional group \( CO \) (specifically a methyl ketone) into a carboxylic acid \( COOH \).

### Step-by-Step Solution:

1. **Identify the Functional Groups**:
- The starting compound has a ketone group (specifically a methyl ketone) at the end of the carbon chain.
- The target compound has a carboxylic acid group.

2. **Understanding the Reaction**:
- We need to convert the ketone \( CO \) into a carboxylic acid \( COOH \). This transformation typically involves oxidation.

3. **Evaluating the Reagents**:
- **Option A: Tollens' Reagent** - This reagent is used to test for aldehydes and cannot oxidize ketones to carboxylic acids. Therefore, it is not suitable.
- **Option B: Benzoyl Peroxide** - This reagent is primarily used in radical reactions and does not facilitate the conversion of a ketone to a carboxylic acid. Thus, it is not suitable.
- **Option C: I2 and NaOH** - This reagent is used in the Iodoform test, which can oxidize methyl ketones to carboxylic acids. This is the correct choice for our conversion.
- **Option D: Tin and NaOH** - This combination is typically used for reductions and cannot achieve the desired oxidation of the ketone to a carboxylic acid. Hence, it is not suitable.

4. **Conclusion**:
- The most suitable reagent for the conversion of \( CH_3-CH=CH-CH_2-CO-CH_3 \) to \( CH_3-CH=CH-CH_2-COOH \) is **I2 and NaOH**.

### Final Answer:
The most suitable reagent for the conversion is **I2 and NaOH**.