Which of the following would not rearrange to a more stable form?

Options

A.
B.
C.
D.

Explanation

To determine which of the given carbocations would not rearrange to a more stable form, we need to analyze the stability of each carbocation and whether they can undergo rearrangement.

### Step-by-Step Solution:

1. **Identify the Carbocations**:
We need to look at the structures of the carbocations provided in the question. Each carbocation has a different degree of substitution (1°, 2°, 3°).

2. **Evaluate Stability**:
- **Carbocation A**: If it is a 2° carbocation, it can rearrange to a more stable 3° carbocation by a hydride shift. Thus, it can rearrange.
- **Carbocation B**: This is a 1° carbocation. If a hydride shifts to it, it can become a 2° carbocation, which is more stable. Therefore, it can rearrange.
- **Carbocation C**: This carbocation is part of a ring structure. If it undergoes a ring expansion, it does not rearrange in the traditional sense (like hydride shifts). Instead, it expands into a larger ring. Therefore, it does not rearrange to a more stable carbocation.
- **Carbocation D**: This is a 2° carbocation. If a hydride shifts, it can rearrange to a more stable 3° carbocation.

3. **Conclusion**:
Based on the analysis, the carbocation that would not rearrange to a more stable form is **Carbocation C**.

### Final Answer:
**Carbocation C** would not rearrange to a more stable form.

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