In the salt equilibrium, why did the addition of HCl cause a solid to form?

NaCl(s)⇄Na+(aq)+Cl⁻(aq)

a. The addition of HCl caused an increase in reactants, so the reaction shifted toward products.
b. The addition of HCl caused an increase in the products, so the reaction shifted toward reactants.
c. The addition of HCl caused a decrease in the reactants, so the reaction shifted toward reactants.
d. The addition of HCl caused a decrease in the products, so the reaction shifted toward products.