In the reaction, if the hybridisation of carbon atom(s) in the product is ${\mathrm{sp}}^3,\mathrm{X}$ is not

If the hybridisation of carbon atom in the product is ${\mathrm{sp}}^3$, it means the product has no unsaturation present in it. It must be saturated in nature like alkane, alcohol etc.

${\mathrm{H}}_2/\mathrm{Ni}$ is to convert a double or triple bond into a single bond.

$\mathrm{HCl}/{\mathrm{AlCl}}_3$ is used in addition reactions to remove unsaturation.

${\mathrm{O}}_3/\mathrm{Zn}+{\mathrm{H}}_2\mathrm{O}$ is used in ozonolysis reactions to give aldehyde or ketone.

${\mathrm{Br}}_2/{\mathrm{CCl}}_4$ is used in anti-addition of bromine reaction.