Amixture of reactants and products for the reaction shown below is at equilibrium

Amixture of reactants and products for the reaction shown below is at
equilibrium in a 1.0 l container. what would happen to the equilibrium if argon gas were added to the container?
n2(g)+ 3h2(g) -> 2nh3(9)

a. more n2 and hy would be produced until equilibrium was reached.
b. less n2, h2, and nh3 would be produced until equilibrium was
reached.
c. more nh3 would be produced until equilibrium was reached.
d. the concentrations of n2, h2, and nh3 would remain the same.