`O-`Crsol `&` benzyl alcohol are

Options

A. Fuctional isomers
B. Position isomers
C. Chain isomers
D. All the above

Explanation

To determine the relationship between O-cresol and benzyl alcohol, we will analyze their structures and functional groups step by step.

### Step 1: Identify the Structures
- **O-cresol**: O-cresol, also known as ortho-cresol, is a phenolic compound where a hydroxyl group (-OH) is attached to a benzene ring that has a methyl group (-CH₃) on the adjacent carbon. Its structure can be represented as follows:
```
OH
|
C6H4-CH3
```
- **Benzyl Alcohol**: Benzyl alcohol consists of a benzene ring with a hydroxymethyl group (-CH₂OH) attached to it. Its structure can be represented as:
```
OH
|
C6H5-CH2
```

### Step 2: Analyze Functional Groups
- **O-cresol**: The functional group is the hydroxyl group (-OH) attached to a carbon in the benzene ring.
- **Benzyl Alcohol**: The functional group is also the hydroxyl group (-OH), but it is attached to a carbon that is connected to a benzene ring through a -CH₂- group.

### Step 3: Determine the Type of Isomerism
- **Functional Isomers**: Compounds that have the same molecular formula but different functional groups or arrangements of atoms. In this case, both O-cresol and benzyl alcohol have the same molecular formula (C₇H₈O) but different functional groups (phenolic vs. benzylic).
- **Positional Isomers**: Compounds that have the same molecular formula and functional group but differ in the position of the functional group on the carbon chain. This does not apply here as the functional groups are different.
- **Chain Isomers**: Compounds that differ in the arrangement of the carbon skeleton. This is not applicable as both compounds contain a benzene ring.

### Conclusion
Based on the analysis, O-cresol and benzyl alcohol are **functional isomers** because they have the same molecular formula but different functional groups.

### Final Answer
O-cresol and benzyl alcohol are **functional isomers**.

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