`C_(6)H_(5)NH_(2)overset(NaNO_(2)//HCl)rarrXoverset(Cu_(2)(CN)_(2))rarrYoverset(H_(2)O//H^(+))rarrZ` Z is identified as

Options

A. `C_(6)H_(5)-NH-CH_(3)`
B. `C_(6)H_(5)-COOH`
C. `C_(6)H_(5)-CH_(2)-NH_(2)`
D. `C_(6)H_(5)-CH_(2)-COOH`

Explanation

To solve the problem step by step, we will analyze the reactions taking place in the sequence provided in the question.

### Step 1: Identify the starting compound
The starting compound is aniline, which is represented by the formula \( C_6H_5NH_2 \).

### Step 2: Reaction with NaNO2 and HCl
When aniline reacts with sodium nitrite (\( NaNO_2 \)) in the presence of hydrochloric acid (\( HCl \)), it undergoes diazotization to form a diazonium salt. The reaction can be represented as follows:

\[ C_6H_5NH_2 + NaNO_2 + HCl \rightarrow C_6H_5N_2^+Cl^- + NaCl + 2H_2O \]

The product formed is benzene diazonium chloride (\( C_6H_5N_2^+Cl^- \)), which we will denote as \( X \).

### Step 3: Reaction with \( Cu_2(CN)_2 \)
Next, the benzene diazonium chloride (\( X \)) reacts with \( Cu_2(CN)_2 \) (copper(I) cyanide) to undergo a coupling reaction, leading to the formation of a cyanobenzene derivative. The reaction can be represented as:

\[ C_6H_5N_2^+Cl^- + Cu_2(CN)_2 \rightarrow C_6H_5CN + N_2 + CuCl \]

Here, \( C_6H_5CN \) is benzonitrile, which we will denote as \( Y \).

### Step 4: Hydrolysis of \( Y \)
The final step involves the hydrolysis of benzonitrile (\( Y \)). When benzonitrile is hydrolyzed in the presence of water and an acid (\( H^+ \)), it converts into benzoic acid. The reaction can be represented as:

\[ C_6H_5CN + H_2O \xrightarrow{H^+} C_6H_5COOH \]

The product formed is benzoic acid, which we will denote as \( Z \).

### Conclusion
Thus, the final compound \( Z \) is identified as **benzoic acid** (\( C_6H_5COOH \)).

---