A compound (X) has the molecular formula ` C_7 H_7O` . On treatment with ` Br_2` and ` KOH`. (X) gives an amine (Y) , (Y) gives carbylamine lest . (Y) upon diazotisation and couupling with phenol gives an azodye (Z ) .(X) is :
A. `PhCONH_2`
B. `PhCONHCOCH_3`
C. `PhNO_2`
D. `PhCOONH_4`