IIcat of ncutralization of any strong acid by any strong basc is the same because
(1) Basically it is the same reaction taking place in all such cases.
(2) Basically it is the reaction of $\mathrm{H}^{-}+\mathrm{OH} \rightarrow \mathrm{H}_{2} \mathrm{O}$
(3) Strong acids and strong bases ionize completely in water.
(4) All the above.