A general mechanism for aromatic electrophilic substitution reaction is. (`K_(1)` and `K_(2)` are rate constant for the forward reaction) also C-D bond in harder to break than a C-H bond, and consequently reaction in which C-D bond broken proceed more slowly than the reaction in which C-H bond are broken. However experimetns reveal that nitration of `C_(6)H_(6) and C_(6)D_(6)` proceeds at equal rates while the same is not true for sulphonation of `C_(6)H_(6)` and `C_(6)D_(6)`. Q. What can be inferred regarding mechanism of sulphonation of `C_(6)H_(6) and C_(6)D_(6)`A. Activation energy for the first step in `C_(6)H_(6)` is greater than that of `C_(6)D_(6)`B. Activation energy for the first step in `C_(6)H_(6)` is smaller than that of `C_(6)D_(6)`C. When benzene is sulphonated, Ea (i) and Ea (ii) are closer than they are when `C_(6)D_(6)` is sulphonated.D. When `C_(6)D_(6)` is sulphonated Ea (i) and Ea (ii) comes very close and `K_(2)` approaches `K_(1)`.