Among $\mathrm{C}, \mathrm{S}$ and $\mathrm{P}$, the element (s) that produce (s) ${\mathrm{SO}}_2$ on reaction with hot conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ is/are

The reactions between given elements, $\mathrm{S}, \mathrm{C}$ and $\mathrm{P}$ with conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ are as follows:

$\mathrm{C}+{\mathrm{H}}_2{\mathrm{SO}}_4⟶{\mathrm{CO}}_2+{\mathrm{SO}}_2+{\mathrm{H}}_2\mathrm{O}$

$\mathrm{S}+{\mathrm{H}}_2{\mathrm{SO}}_4⟶{\mathrm{SO}}_2+{\mathrm{H}}_2\mathrm{O}$

${\mathrm{P}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4⟶{\mathrm{H}}_3{\mathrm{PO}}_4+{\mathrm{SO}}_2+{\mathrm{H}}_2\mathrm{O}$

Thus, all the given elements produces ${\mathrm{SO}}_2$ on reaction with hot concentration.