64. A result of the common-ion effect is ________. (A)that some ions, such as Na+ (aq), frequently appear in solutions but do not participate in solubility equilibria (B)that common ions, such as Na+ (aq), don't affect equilibrium constants (C) that the selective precipitation of a metal ion, such as Ag+, is promoted by the addition of an appropriate counterion (X-) that produces a compound (AgX) with a very low solubility (D)that ions such as K+ and Na+ are common ions, so that their values in equilibrium constant expressions are always 1.00