Answer:
The reverse reaction is favoured
Step-by-step explanation:
According to the principle; when a constraint such as a change in concentration, pressure, temperature etc is imposed on a reaction system in equilibrium, the equilibrium position will shift in such a direction as to annul the constraint.
In this case, the constraint is a change in volume. If the volume is decreased, the reverse reaction (leading to less total volume) is favoured.
The forward reaction leads to four volumes while the reverse reaction leads to only two volumes. Decrease in volume favours the direction in which the total volume is lower.