` A 10 L "container at" 300K "contains" CO_(2) "gas at pressure of" 0.2 "atm and and excess solid" CaO ("neglect the volume of solid" CaO)`. The volume of container is now decreased by moving the movable piston fitted in the container. What will be the maximum volume of container when pressure of `CO_(2)` attains its maximum value given that `CaCO_(3)(s)hArrCaO(s)+CO_(2)(g) K_(P)=0.800 "atm"`
A. `5L`
B. `2.5L
C. `1L`
D. The information is insufficient.