The compound (C) in the given sequence of reaction is ,
`C_6H_5OHoverset(NaOH)rarr(A)overset(CO_2)rarr(B)overset(HCl)rarr(C)`

Options

A. chlorobenzene
B. Benzoic acid
C. Salicyladehyde
D. Salicylic acid

Answer

To determine the compound (C) in the given sequence of reactions, we will analyze each step of the reactions involving phenol (C6H5OH).

### Step-by-Step Solution:

1. **Identify the starting compound:**
The starting compound is phenol, which has the molecular formula C6H5OH.

2. **Reaction with Sodium Hydroxide (NaOH):**
When phenol reacts with sodium hydroxide, it forms the sodium salt of phenol. This is a deprotonation reaction where the hydroxyl (-OH) group of phenol loses a hydrogen ion (H+) and forms sodium phenoxide (C6H5O^- Na^+).

**Reaction:**
C6H5OH + NaOH → C6H5O^- Na^+ + H2O

**Intermediate (A):** Sodium phenoxide (C6H5O^- Na^+)

3. **Reaction with Carbon Dioxide (CO2):**
The sodium phenoxide then reacts with carbon dioxide under specific conditions (high temperature and pressure). This reaction is known as the Kolbe-Schmitt reaction, which results in the formation of sodium salicylate.

**Reaction:**
C6H5O^- Na^+ + CO2 → C6H4(OH)(COO^- Na^+) (sodium salicylate)

**Intermediate (B):** Sodium salicylate (C6H4(OH)(COO^- Na^+))

4. **Reaction with Hydrochloric Acid (HCl):**
Finally, when sodium salicylate is treated with hydrochloric acid, it leads to the formation of salicylic acid by protonating the carboxylate group.

**Reaction:**
C6H4(OH)(COO^- Na^+) + HCl → C6H4(OH)(COOH) + NaCl

**Final Compound (C):** Salicylic acid (C6H4(OH)(COOH))

### Conclusion:
The compound (C) in the given sequence of reactions is **salicylic acid**.