i. Four DU in (A) and `(C:H~~1:1)` suggest benzene ring.
ii. (A) `overset ([O]) rarr` Benzoinc acid, it suggests that it is a monosubstitude benzene derive.
iii. The reaction with Na suggests (OH) group in the side chain. Possible structures are:
Therefore, structure of (A) is (IV) (2-phenyl propan-1-ol).