${\mathrm{Cs}}_2$  reacts with ${\mathrm{Cl}}_2$  to produce :

Chlorine reacts with carbon disulfide to form carbon tetrachloride

$\begin{array}{r}{\mathrm{CS}}_2+3{\mathrm{Cl}}_2\to {\mathrm{CCl}}_4+{\mathrm{S}}_2{\mathrm{Cl}}_2\\ 2{\mathrm{S}}_2{\mathrm{Cl}}_2+{\mathrm{CS}}_2\to {\mathrm{CCl}}_4+6\mathrm{S}\end{array}$

Hence, the correct option is A.