Which of the following is an example of nucleophilic addition ?

Options

A. `{:(" "O" "N-NH_(2)),(" || ||"),(CH_(3)-C-CH_(3)overset(NH_(2)NH_(2),H^(+))rarrCH_(3)-C-CH_(3)):}`
B. `CH_(3)-overset(O)overset(||)C-CH_(3)overset(LiAlH_(4))rarrCH_(3)-overset(OH)overset("| ")"CH"-CH_(3)`
C. `{:(" "O" "N-NH_(2)),(" || ||"),(CH_(3)-C-CH_(3)overset(NH_(2)NH_(2),H^(+))rarrCH_(3)-C-CH_(3)):}` and `CH_(3)-overset(O)overset(||)C-CH_(3)overset(LiAlH_(4))rarrCH_(3)-overset(OH)overset("| ")"CH"-CH_(3)`
D. None of the two

Answer

To determine which of the given options is an example of a nucleophilic addition reaction, we need to understand the concept of nucleophiles and the mechanism of nucleophilic addition.

### Step-by-Step Solution:

1. **Understanding Nucleophiles**:
- A nucleophile is a species that has a pair of electrons to donate, making it electron-rich. Common nucleophiles include anions or neutral molecules with lone pairs of electrons.

2. **Identifying Carbonyl Compounds**:
- Nucleophilic addition typically occurs with carbonyl compounds (like aldehydes and ketones) because the carbon atom in the carbonyl group (C=O) is electron-deficient due to the electronegativity of oxygen.

3. **Analyzing the Options**:
- We need to analyze the given options (though not provided here, we will assume common examples) to identify which one involves a nucleophile attacking a carbonyl carbon.

4. **Example of Nucleophilic Addition**:
- For instance, if we consider acetone reacting with ammonia (NH2), the nitrogen atom from ammonia acts as a nucleophile and attacks the carbonyl carbon of acetone. This leads to the formation of an intermediate where the carbonyl oxygen becomes negatively charged (alkoxide ion).

5. **Formation of Product**:
- The intermediate can then undergo protonation (gaining a proton) and rearrangement, leading to the formation of an amine or an alcohol, depending on the specific reaction conditions.

6. **Conclusion**:
- If both acetone with ammonia and lithium aluminum hydride (LiAlH4) reducing a ketone to an alcohol are options, both represent nucleophilic addition reactions. The hydride ion (H-) from LiAlH4 acts as a nucleophile, attacking the carbonyl carbon and resulting in the formation of an alcohol.

### Final Answer:
Both A (acetone with ammonia) and B (lithium aluminum hydride reducing a ketone) are examples of nucleophilic addition reactions.

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