Which of the following reactions depict the oxidising behavior of ${\mathrm{H}}_2{\mathrm{SO}}_4?$

The oxidation state of sulphur in the anions ${\mathrm{SO}}_3^{2-}$, ${\mathrm{SO}}_4^{2-}$, ${\mathrm{S}}_2{\mathrm{O}}_4^{2-}$ and ${\mathrm{S}}_2{\mathrm{O}}_6^{2-}$ follows the order

Consider the following reaction to prepare labile thiosulphate ${\mathrm{SO}}_3^{2-}{+}_{16}^{35}\mathrm{S}\stackrel{\mathrm{Boil}}{\to }{}_{16}{}^{35}\mathrm{SSO}_3^{2-}$ $\left({}_{16}{}^{35}\mathrm{S}=\text{ labile sulphur, }\mathrm{S}=\text{ normal sulphur }\right)$

If, thiosulphate so formed is decomposed by treatment with dilute ${\mathrm{H}}_2{\mathrm{SO}}_4$ or dilute HCl, then

In which of the following rea

ctions concentrated ${\mathrm{H}}_2{\mathrm{SO}}_4$ is used as an oxidising reagent?