When bromo benzene is monochlorinated, two Isomeric compounds `A` and `B` are obtained. Monobromination of `A` gives several isomeric products of molecular formula `C_6 H_3 CI Br_2`, while monobromination of `B` yields only 2 isomers `C` and `D`. Compound `C` is identical with one of the compounds obtained from bromination of `A`, however` D `is totally different from any of the isomeric cómpounds obtained from the bromination of `A`, Give structures of ` A, B, C` and ` D` and also structures of four isomeric monobrominated products of `A` Support your answer with reasoning.