12. In which equilibrium system will an increase in pressure cause a shift to the left?
A) C + O2(8) + CO2(8)
C) 2 Mg(s) + O2(8) + 2 MgO)
B) CaCO3s) <> CaO + CO2g)
D) 2 H2(g) + O2(g) + 2 H2O)