$\underset{\mathrm{Slat} \mathrm{of} \mathrm{iron}}{X}\stackrel{N{a}_2{S}_2{O}_3}{\to }$$\underset{\mathrm{Violet} \mathrm{complex} }{\mathit{\left(}Y\mathit{\right)}}\stackrel{ }{\to }$$\underset{\mathrm{Green} \mathrm{aclutlon} }{Z}$

Write oxidation number of $\mathrm{Fe}$ in $\mathit{\left(}X\mathit{\right)}$ as first digit, $\mathit{\left(}Y\mathit{\right)}$ as second digit, $\mathit{\left(}Z\mathit{\right)}$ as third digit in $\mathrm{OMR}$.

The reactions are,

${\mathrm{Fe}}^{3+}+{\mathrm{S}}_2{\mathrm{O}}_3^{2-}⟶\underset{(\mathrm{Violet} \mathrm{Coloured} \mathrm{complex})}{{\left[\mathrm{Fe}{\left({\mathrm{S}}_2{\mathrm{O}}_3\right)}_2\right]}^{-}}$

${\left[\mathrm{Fe}{\left({\mathrm{S}}_2{\mathrm{O}}_3\right)}_2\right]}^{-}+{\mathrm{Fe}}^{3+}\stackrel{\text{ Boil }}{⟶}2{\mathrm{Fe}}^{2+}+{\mathrm{S}}_4{\mathrm{O}}_6^{2-}$

Thus,

$2{\mathrm{Fe}}^{3+}+{\mathrm{S}}_2{\mathrm{O}}_3^{2-}⟶2{\mathrm{Fe}}^{2+}\text{ (green) }+{\mathrm{S}}_4{\mathrm{O}}_6^{2-}$

Here, oxidation state of components are,

$$\begin{gathered} X\to 3, \\ Y\to 3, \\ Z\to 2 \end{gathered}$$

Thus, the correct answer is 332.