How would decreasing the volume of the reaction vessel affect each of the following equilibria?

Increasing the pressure inside the reaction vessel will cause the equilibrium to shift in such a way as to reduce this increase in pressure. ... As a result, the equilibrium will shift to the left, i.e. it will favor the reverse reaction, since that's the side that contains the fewer moles of gas.Jul 19, 2016

Ithink it’s 3 as the answer.