Water Gas, a Commercial Fuel, Is Made by the Reaction

Water gas, a commercial fuel, is made by the reaction of hot coke carbon with steam.C(s) + H₂O(g) → CO(g) + H₂(g)
When equilibrium is established at 800°C, the concentrations of CO, H₂, and H₂O are 4.00 × 10^-2 mol/L, 4.00 × 10^-2 mol/L, and 1.00 × 10^-2 mol/L, respectively. Calculate the value of ΔG° for this reaction at 800°C.

A) 16.3 kJ
B) 109 kJ
C) 193 kJ
D) -43.5 kJ
E) none of these