Assertion: `(CH_(3))_(3)C COC(CH_(3))_(3)` and acetone can be distanguished by the reaction with `NaHSO_(3)`.
Reason : `HSO_(3)` is the nucleophile in bisulphite addition.

Options

A. if both assertion and reason are true and reason is thr correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reson are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that `(CH₃)₃C COC(CH₃)₃` (which is a highly substituted ketone) and acetone can be distinguished by their reaction with sodium bisulfite (`NaHSO₃`).

### Step 2: Analyze the Reaction with Sodium Bisulfite
When acetone reacts with sodium bisulfite, it forms a bisulfite adduct and releases sulfur dioxide (SO₂) gas, which can be observed as effervescence. This reaction occurs because acetone is a simple ketone that can easily react with the nucleophile.

### Step 3: Reaction with the Highly Substituted Ketone
On the other hand, the highly substituted ketone `(CH₃)₃C COC(CH₃)₃` is sterically hindered. This steric hindrance prevents the nucleophile (HSO₃⁻) from approaching and reacting with it. Therefore, there will be no effervescence of sulfur dioxide when sodium bisulfite is added to this ketone.

### Step 4: Conclusion on the Assertion
Since acetone reacts with sodium bisulfite and releases SO₂, while the highly substituted ketone does not react, the assertion is true.

### Step 5: Understand the Reason
The reason states that `HSO₃` is the nucleophile in bisulfite addition. This is also true, as HSO₃⁻ is indeed the nucleophile that attacks the carbonyl carbon of the ketone.

### Step 6: Evaluate the Relationship between Assertion and Reason
While both statements are true, the reason does not adequately explain why the assertion is true. The assertion is about the ability to distinguish between the two ketones, while the reason merely states the identity of the nucleophile without addressing the steric hindrance that affects the reaction with the highly substituted ketone.

### Final Conclusion
- The assertion is true.
- The reason is true but does not correctly explain the assertion.
- Therefore, the correct answer is that the assertion is true, and the reason is true but not the correct explanation.