Which one of the compound is not isomers of others?

Options

A.
B.
C.
D.

Explanation

To determine which compound is not an isomer of the others, we need to follow these steps:

### Step 1: Identify the Molecular Formula of Each Compound
We need to analyze the molecular formula of each compound presented in the question. Isomers must have the same molecular formula.

- **Compound A**: C8H14
- **Compound B**: C8H14
- **Compound C**: C8H14
- **Compound D**: C8H12

### Step 2: Compare the Molecular Formulas
Next, we compare the molecular formulas of all the compounds:

- Compounds A, B, and C all have the molecular formula C8H14.
- Compound D has the molecular formula C8H12.

### Step 3: Determine Isomerism
Since isomers are defined as compounds that have the same molecular formula but different structural arrangements, we can conclude:

- Compounds A, B, and C are isomers of each other because they share the same molecular formula (C8H14).
- Compound D is not an isomer of the others because it has a different molecular formula (C8H12).

### Conclusion
The compound that is not an isomer of the others is **Compound D**.

### Final Answer
**D** is the compound that is not an isomer of the others.

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