Step 1: Identify the named reaction:
Phenol, CCl4 and aqueous NaOH is the CCl4 variant of the Reimer-Tiemann reaction. With CHCl3 the product would be an aldehyde; with CCl4 it is a carboxylic acid.
Step 2: Follow the groups:
The ring gets $-\text{CCl}_3$ ortho to OH. Alkali hydrolyses $-\text{CCl}_3$ to $-\text{COONa}$, so B is sodium salicylate. Acid then gives the free acid.
Step 3: Choose the structure:
The product has $-\text{OH}$ and $-\text{COOH}$ on neighbouring carbons, i.e. salicylic acid. That is option (B). The CHO option corresponds to CHCl3, the diol option would need hydroxylation, and the CH3 option would need reduction, so they are all wrong.
Final Answer:
C is salicylic acid.
\[ \boxed{\text{Option (B)}} \]
