The correct set of the products obtained in the following reactions
`RCNoverset("reduction")rarr(A),RCNunderset((ii)H_(2)O)overset((i)CH_(3)MgBr)rarr(B), RNCoverset("hydrolysis")rarr(C),RNH_(2)overset(HNO_(2))rarr(D)`
The answer is :

Options

A. `{:(,A,B,C,D),((A), 2^(@)"Amine","Methyl ketone",1^(@) "Amine","Alcohol"):}`
B. `{:(,A,B,C,D),((B),1^(@) "Amine","Methyle ketone",1^(@) "Amine","Alcohol"):}`
C. `{:(,A,B,C,D),((C),2^(@)"Amine","Methyl ketone",2^(@) "Amine","Acid"):}`
D. `{:(,A,B,C,D),((D),2^(@)"Amine","Methyl ketone",2^(@) "Amine","Aldehyde"):}`

Answer

To solve the given question, we need to analyze each reaction step by step and identify the products formed.

### Step-by-Step Solution:

1. **Reduction of Cyanide (RCN → A)**:
- When a cyanide (RCN) is reduced, it typically leads to the formation of a primary amine (RNH₂).
- **Product A**: Primary amine (RNH₂).

**Hint**: Remember that reducing agents add hydrogen, converting the cyanide group into an amine.

2. **Reaction with Grignard Reagent (RCN + CH₃MgBr → B)**:
- In this reaction, the cyanide (RCN) reacts with a Grignard reagent (methyl magnesium bromide, CH₃MgBr).
- This reaction results in the formation of a ketone. Specifically, it forms a methyl ketone (RCOCH₃) after hydrolysis.
- **Product B**: Methyl ketone (RCOCH₃).

**Hint**: Grignard reagents react with carbonyl compounds to form alcohols, but here it forms a ketone after hydrolysis.

3. **Hydrolysis of Isocyanide (RNC → C)**:
- Hydrolysis of isocyanide (RNC) leads to the formation of a primary amine (RNH₂).
- **Product C**: Primary amine (RNH₂).

**Hint**: Hydrolysis typically involves the addition of water, which can convert isocyanides back to amines.

4. **Reaction of Primary Amine with Nitrous Acid (RNH₂ + HNO₂ → D)**:
- When a primary amine (RNH₂) reacts with nitrous acid (HNO₂), the products formed are typically an alcohol, nitrogen gas, and water.
- The primary amine is converted into a primary alcohol (R-OH).
- **Product D**: Primary alcohol (R-OH).

**Hint**: The reaction with nitrous acid is a classic reaction that leads to the formation of alcohols from amines.

### Final Products:
- **A**: Primary amine (RNH₂)
- **B**: Methyl ketone (RCOCH₃)
- **C**: Primary amine (RNH₂)
- **D**: Primary alcohol (R-OH)

### Conclusion:
The correct set of products obtained from the reactions is:
- A: Primary amine
- B: Methyl ketone
- C: Primary amine
- D: Primary alcohol

The answer is option number B.