Which of the following is least stable ?

Options

A. `CH_3-CH^(+)-CH_3`
B. `CH_3CH_2-CH_2^(+)`
C. `CH_3-C(CH_3)^(+)-CH_3`
D. `(CH_3)_3C-C(C_6H_5)H^(+)`

Explanation

To determine which of the given carbocations is the least stable, we need to analyze the stability of each type of carbocation based on the number of alkyl groups attached to the positively charged carbon atom.

### Step-by-Step Solution:

1. **Identify the Types of Carbocations**:
- Carbocations can be classified based on the number of alkyl groups attached to the positively charged carbon atom:
- **Primary (1°) Carbocation**: Carbon attached to one alkyl group.
- **Secondary (2°) Carbocation**: Carbon attached to two alkyl groups.
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