Identify B, X and R respectively in the following sequence of reactions
`C_(2)H_(5)MgBroverset(ClCN)rarrAoverset(H_(3)O^(+))rarrB`,
`CH_(3)COCH_(3)underset(NaOH)overset(I_(2))rarrXoverset(Ag)rarrY`
`C_(6)H_(5)NH_(2)underset(HCl)overset(NaNO_(2))rarrPoverset(CuCN)rarrQoverset(+4H)rarrR`

Options

A. `C_(2)H_(5)COOH, CHI_(3),C_(6)H_(5)CH_(2)NH_(2)`
B. `C_(2)H_(5)COOH, CH_(3)I, C_(6)H_(5)COOH`
C. `C_(2)H_(5)CH_(2)NH_(2), CH_(3I, C_(6)H_(5)COOH`
D. `C_(2)H_(5)COOH, C_(2)H_(5)I, C_(6)H_(5)CONH_(2)``C_(2)H_(5)COOH, C_(2)H_(5)I, C_(6)H_(5)CONH_(2)`

Answer

To identify the compounds B, X, and R in the given sequence of reactions, let's analyze each step carefully.

### Step 1: Identify Compound A
The first reaction involves ethyl magnesium bromide (C2H5MgBr) reacting with acetonitrile (ClCN). This reaction is a Grignard reaction leading to the formation of a nitrile.

- **Reaction**:
\[ C_2H_5MgBr + ClCN \rightarrow C_2H_5CN \quad (A) \]
- **Product A**: Ethyl cyanide (C2H5CN)

### Step 2: Identify Compound B
The next step involves the hydrolysis of compound A (C2H5CN) using acid (H3O+). This reaction converts the nitrile into a carboxylic acid.

- **Reaction**:
\[ C_2H_5CN + H_3O^+ \rightarrow C_2H_5COOH \quad (B) \]
- **Product B**: Ethanoic acid (C2H5COOH)

### Step 3: Identify Compound X
The next reaction involves acetone (CH3COCH3) undergoing a haloform reaction in the presence of iodine (I2) and sodium hydroxide (NaOH). This reaction produces methyl iodide (CH3I).

- **Reaction**:
\[ CH_3COCH_3 + I_2 + NaOH \rightarrow CH_3I \quad (X) \]
- **Product X**: Methyl iodide (CH3I)

### Step 4: Identify Compound Y
The reaction of methyl iodide (X) with silver (Ag) leads to the formation of acetylene (C2H2).

- **Reaction**:
\[ CH_3I + 6Ag \rightarrow C_2H_2 \quad (Y) \]
- **Product Y**: Acetylene (C2H2)

### Step 5: Identify Compound P
The next reaction involves aniline (C6H5NH2) reacting with sodium nitrite (NaNO2) in hydrochloric acid (HCl) to form benzene diazonium chloride (C6H5N2Cl).

- **Reaction**:
\[ C_6H_5NH_2 + NaNO_2 + HCl \rightarrow C_6H_5N_2Cl \quad (P) \]
- **Product P**: Benzene diazonium chloride (C6H5N2Cl)

### Step 6: Identify Compound Q
The diazonium salt (P) reacts with copper cyanide (CuCN) to form phenyl cyanide (C6H5CN).

- **Reaction**:
\[ C_6H_5N_2Cl + CuCN \rightarrow C_6H_5CN \quad (Q) \]
- **Product Q**: Phenyl cyanide (C6H5CN)

### Step 7: Identify Compound R
Finally, the reaction of phenyl cyanide (Q) with hydrogen (H2) in the presence of a catalyst (4H) leads to the formation of benzylamine (C6H5CH2NH2).

- **Reaction**:
\[ C_6H_5CN + 4H \rightarrow C_6H_5CH_2NH_2 \quad (R) \]
- **Product R**: Benzylamine (C6H5CH2NH2)

### Summary of Identifications
- **B**: Ethanoic acid (C2H5COOH)
- **X**: Methyl iodide (CH3I)
- **R**: Benzylamine (C6H5CH2NH2)