A : Aldehydes and ketones undergo nucleophilic addition reaction.
R : Aldehydes and ketones contain carbonyl group.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To solve the question, we need to analyze the two statements provided:

**Assertion (A)**: Aldehydes and ketones undergo nucleophilic addition reactions.
**Reason (R)**: Aldehydes and ketones contain a carbonyl group.

### Step-by-step Solution:

1. **Understanding the Assertion**:
- Aldehydes and ketones are known to undergo nucleophilic addition reactions. This is a fundamental reaction type for these compounds due to the presence of the carbonyl group (C=O).
- In nucleophilic addition, a nucleophile attacks the electrophilic carbon atom of the carbonyl group, leading to the formation of an addition product.

2. **Analyzing the Reason**:
- The reason states that aldehydes and ketones contain a carbonyl group. This is indeed true, as both functional groups are characterized by the presence of the C=O bond.
- The carbonyl group is responsible for the reactivity of aldehydes and ketones, making them susceptible to nucleophilic attack.

3. **Evaluating the Relationship**:
- While both the assertion and reason are true, the reason does not directly explain why aldehydes and ketones undergo nucleophilic addition reactions. The reason simply states a fact about the structure of aldehydes and ketones, but does not elaborate on the mechanism of the nucleophilic addition itself.

4. **Conclusion**:
- Since both the assertion and reason are true, but the reason does not serve as a correct explanation for the assertion, the correct option is that both statements are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
The correct option is **Option 2**: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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