The dissociation of phosgene, which occurs according to the reaction
`COCI_(2)(g)hArrCO(g)+CI_(2)(g)`
Is an endothermic process. Which of the following will increase the degree of dissociation of `COCI_(2)?`
A. adding `CI_(2)` to the system
B. Adding helium to the system at constant pressure
C. Decreasing the temperature of the system
D. Reducing the total pressure