Compound A `(C_(7) H_(7)Cl)` react with aq. KOH at room temperature and give compound `D(C_(7)H_(8) O)`. Another isomer B gives only one mononitration product on treatment with `HNO_(3) + H_(2)SO_(4)` mixture . Isomer C gives comound `E(C_(7)H_(5)O_(2)Cl)` on heating with `KMnO_(4)` solution . E gives 3-chloro-4-nitrobezoic acid as major product . Identify compound D.
A.
B.
C.
D.