`CH_(3)-underset(O)underset(||)(C)-CH_(3)+underset(("semicarbazide"))(NH_(2)-underset(O)underset(||)(C)-NH-NH_(2)overset(H^(o+))(to)`
major product is

Options

A. `CH_(3)-underset(O)underset(||)(C)-CH=underset(NH_(2))underset(|)(C)-NH-NH_(2)`
B. `CH_(3)-underset(CH_(3))underset(|)(C)=N-NHunderset(O)underset(||)(C)-NH_(2)`
C. `CH_(3)-underset(CH_(3))underset(|)(C)=N-underset(O)underset(||)(C)-NH-NH_(2)`
D.

Answer

To solve the given question, we need to analyze the reaction between a ketone and semicarbazide under acidic conditions. Let's break down the steps involved in this reaction.

### Step-by-Step Solution:

1. **Identify the Reactants**:
The reactants in the question are:
- A ketone: CH₃C(=O)CH₃ (which is acetone)
- Semicarbazide: NH₂C(=O)NHNH₂

2. **Understand the Reaction Mechanism**:
When a ketone reacts with semicarbazide, a condensation reaction occurs. This involves the formation of a semicarbazone. In this reaction, a water molecule (H₂O) is eliminated.

3. **Write the General Reaction**:
The general reaction can be represented as:
\[ \text{R}_2C=O + \text{NH}_2C(=O)NHNH_2 \xrightarrow{H^+} \text{R}_2C=N-NH-C(=O)NH_2 + H_2O \]
Here, R represents the alkyl groups from the ketone.

4. **Draw the Structure of the Ketone**:
The ketone (acetone) can be represented as:
\[ \text{CH}_3-C(=O)-\text{CH}_3 \]

5. **Draw the Structure of Semicarbazide**:
The structure of semicarbazide is:
\[ \text{NH}_2-C(=O)-\text{NH}-\text{NH}_2 \]

6. **Perform the Reaction**:
- The nitrogen atom from the NH₂ group of semicarbazide attacks the carbonyl carbon of the ketone.
- A water molecule is eliminated, forming a double bond between the carbon and nitrogen.

7. **Final Product Structure**:
The final product after the reaction will have the following structure:
\[ \text{CH}_3-C(=N-NH-C(=O)-NH_2)-\text{CH}_3 \]
This structure represents the semicarbazone of the ketone.

8. **Identify the Major Product**:
The major product formed from this reaction is the semicarbazone, which is a stable compound.

### Conclusion:
The major product of the reaction between the ketone (acetone) and semicarbazide under acidic conditions is:
\[ \text{CH}_3-C(=N-NH-C(=O)-NH_2)-\text{CH}_3 \]