Columns 1, 2 and 3 contain starting materials, reaction conditions and type of reactions respectively.
 

Column 1	Column 2	Column 3
(I) Toulene	(i) $NaOH/B{r}_2$	(P) Condensation
(II) Acetophenone	(ii) $B{r}_2/hv$	(Q) Carboxylation
(III) Benzaldehyde	(iii) ${\left(C{H}_{3}CO\right)}_{2}O/C{H}_{3}COOK$	(R) Substitution
(IV) Phenol	(iv) $NaOH/C{O}_2$	(S) Haloform

For the synthesis of benzoic acid the only correct combination is