Compound `(x)(m.f=C_(7)H_(8)N)`, on reaction with `NaNO_(2)` and conc. `HCl` at `O^(@)C` followed by `beta -` naphthol gives orange coloured dye. Compound `(x)` is `:`

Options

A.
B.
C.
D. All of these

Answer

To solve the problem, we need to identify the compound \( (x) \) with the molecular formula \( C_7H_8N \) that reacts with \( NaNO_2 \) and concentrated \( HCl \) at \( 0^\circ C \) to form an orange-colored azo dye when followed by \( \beta \)-naphthol.

### Step-by-Step Solution:

1. **Understanding the Reaction**: The reaction described involves an aromatic primary amine. This type of amine can react with sodium nitrite (\( NaNO_2 \)) and hydrochloric acid (\( HCl \)) to form a diazonium salt, which can then couple with \( \beta \)-naphthol to produce an azo dye.

2. **Identifying the Structure of Compound \( (x) \)**: The molecular formula \( C_7H_8N \) suggests that the compound is an aromatic primary amine. The simplest aromatic amine is aniline (\( C_6H_5NH_2 \)), which has a phenyl group attached to an amine group. To meet the molecular formula \( C_7H_8N \), we can add a methyl group (\( CH_3 \)) to the aniline structure.

3. **Possible Structures**: The methyl group can be attached to the benzene ring in three possible positions relative to the amine group:
- **Ortho position**: \( C_6H_4(NH_2)(CH_3) \) (1,2-dimethylamine)
- **Meta position**: \( C_6H_4(NH_2)(CH_3) \) (1,3-dimethylamine)
- **Para position**: \( C_6H_4(NH_2)(CH_3) \) (1,4-dimethylamine)

4. **Reactivity with \( NaNO_2 \) and \( HCl \)**: All three structures are aromatic primary amines and will react with \( NaNO_2 \) and \( HCl \) to form the corresponding diazonium salts.

5. **Coupling with \( \beta \)-Naphthol**: The diazonium salt formed will then couple with \( \beta \)-naphthol to form an azo dye. The resulting azo dye will have an orange color, which is characteristic of azo compounds formed from such reactions.

6. **Conclusion**: Since all three structures can potentially lead to the formation of an azo dye, we need to identify which one is the correct compound \( (x) \) based on the options provided.

- After analyzing the options, we find that **Option 2** corresponds to one of the possible structures of \( (x) \) that fits the criteria given in the question.

### Final Answer:
The compound \( (x) \) is **Option 2**.