`2,3-`Dimethyl`-2-`butene can be prepared by heating which of the following compounds with a strong acid ?

Options

A. `(CH_(3))_(2)C=CH-CH_(2)-CH_(2)`
B. `(CH_(3))_(2)CH-CH_(2)-CH=CH_(2)`
C. `(CH_(3))_(2)CH-underset(CH_(3))underset(|)(C)H-CH=CH_(2)`
D. `(CH_(3))_(2)C-CH=CH_(2)`

Explanation

To determine which compound can be heated with a strong acid to prepare 2,3-dimethyl-2-butene, we need to analyze each given compound and see if it can lead to the desired product through carbocation rearrangement and elimination reactions.

### Step-by-Step Solution:

1. **Identify the Structure of the Desired Product:**
- The structure of 2,3-dimethyl-2-butene is:
```
CH3
|
CH3-C=CH-CH3
|
CH3
```
- This compound has a double bond between the second and third carbon atoms, with two methyl groups attached to the second carbon.

2. **Analyze Each Compound:**
- **Option 1: CH3-C(CH3)=CH-CH2-CH3**
- On heating with a strong acid, this compound would form a carbocation. However, the resulting alkene does not match the desired product. Therefore, this option is incorrect.

- **Option 2: CH3-CH2-C(CH3)=O**
- Upon heating with acid, this compound would also rearrange to form a different carbocation. The elimination process would not yield the desired product, so this option is also incorrect.

- **Option 3: CH3-CH=CH-CH3**
- This compound would form a secondary carbocation upon heating with acid. However, it would not lead to the formation of 2,3-dimethyl-2-butene, as it would yield a different alkene. Thus, this option is incorrect.

- **Option 4: CH3-C(CH3)=CH2**
- When this compound is heated with a strong acid, it forms a carbocation. The carbocation can undergo a methyl shift to form a more stable tertiary carbocation. The elimination of a proton from the appropriate carbon leads to the formation of 2,3-dimethyl-2-butene, which is the desired product.

3. **Conclusion:**
- The correct compound that can be heated with a strong acid to yield 2,3-dimethyl-2-butene is **Option 4**.