I. `CH_(3) - CH_(2) - CH_(2) - CH_(2) - OH`
II. `CH_(3) - CH_(2) - underset(OH)underset(|)(CH) - CH_(3)`
III. `CH_(3) - underset(OH) underset(|)overset(CH_(3))overset(|)(C) - CH_(3)`
IV. `CH_(3) - underset(CH_(3))underset(|)(CH) - CH_(2) - OH`
V. `CH_(3) - CH_(2) - O - CH_(2) - CH_(3)`
VI. `CH_(3) - O - CH_(2) - CH_(2) - CH_(3)`
VII. `CH_(3) - O - underset(CH_(3))underset(|)(CH) - CH_(3)`
Identify the pair of compounds that represents chain isomerism

Explanation

To identify the pair of compounds that represent chain isomerism from the given options, we need to follow these steps:

### Step 1: Understand Chain Isomerism
Chain isomers are compounds that have the same molecular formula but different structural formulas, specifically differing in the arrangement of the carbon skeleton (the main chain).

### Step 2: Identify the Molecular Formula
We will first determine the molecular formula of each compound provided in the question.

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