Nucleophilic Aromatic substitution `(SN_(Ar))`:
A substituted benzene derivative containing `- NO_(2)` and `Cl` group at `p-`position is subjected to `Nu-` substitution
Match the column I and II
`{:(,"Column (I)",,"Column (II)",),(,X = "halogen",,"relative reactivity toward" (SN_(Ar)),),((a),-F,(p),312,),((b),-Cl,(q),1,),((c),-Br,(r),0.8,),((d),-I,(s),0.6,):}`