The product obtained from the following sequence of reactions is
`(H_(3)C)_(3)-C-=CH underset(H_(2)SO_(4))overset(HgSO_(4))to A overset (NaBH_(4))rarrB`

Options

A. `(CH_(3))_(3) C - overset(OH)overset(|)(C )HCH_(3)`
B. `(CH_(3))_(3) C - CH = CH_(2)`
C. `(CH_(3))_(2) C = C (CH_(3))_(2)`
D. `(CH_(3))_(3) C - CH_(2) - CH_(2) OH`

Explanation

To solve the given problem, we will follow the sequence of reactions step by step.

### Step 1: Identify the starting compound
The starting compound is `(H3C)3-C≡CH`, which can be represented as:
- **(CH3)3C≡CH** (2-methyl-1-butyne).

### Step 2: Reaction with H2SO4 and HgSO4
The first step involves the reaction of `(H3C)3-C≡CH` with sulfuric acid (H2SO4) and mercuric sulfate (HgSO4). This reaction is known as the hydration of alkynes, which leads to the formation of an enol that will tautomerize to a ketone.

1. The triple bond will undergo hydration, where the mercuric ion (Hg2+) adds to one carbon of the triple bond, forming a carbocation.
2. The more stable carbocation will form on the more substituted carbon. Here, the carbocation will form on the carbon adjacent to the triple bond (2° carbocation).
3. Water (from H2SO4) will then attack this carbocation, leading to the formation of an enol.

The structure after this step will be:
- **(CH3)3C-CH=OH** (2-methyl-2-buten-1-ol).

### Step 3: Tautomerization
The enol formed in the previous step will undergo tautomerization to form a ketone. The hydrogen from the hydroxyl group will shift to the adjacent carbon, and the double bond will shift to form a carbonyl group.

The tautomerization will yield:
- **(CH3)3C=O** (2-methyl-2-butanone).

This compound is our product A.

### Step 4: Reaction with NaBH4
The next step involves the reduction of the ketone (2-methyl-2-butanone) with sodium borohydride (NaBH4), which is a mild reducing agent.

1. Sodium borohydride will reduce the carbonyl group (C=O) of the ketone to form an alcohol.
2. The reduction will yield:
- **(CH3)3C-OH** (2-methyl-2-butanol).

This compound is our product B.

### Final Product
Thus, the final product obtained from the sequence of reactions is **(CH3)3C-OH** (2-methyl-2-butanol).

### Answer
The product obtained from the following sequence of reactions is **(CH3)3C-OH**.

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