Answer:
Rate of forward reaction will increase.
Explanation:
Effect of change in reaction condition on equilibrium is explained by Le Chatelier's principle. According to this principle,
If an equilibrium condition of a dynamic reversible reaction is disturbed by changing concentration, temperature, pressure, volume, etc, then reaction will move will in a direction which counteract the change.
In the given reaction,
A + B ⇌ C + D
If concentration of A is increase, then reaction will move in a direction which decreases the concentration of A to reestablish the equilibrium.
As concentration A decreases in forward direction, therefore, rate of forward reaction will increase.