71. What is the stoichiometry of ion transport per ATP hydrolyzed by the Na⁺/K⁺ pump?(A) 3 Na⁺ out / 2 K⁺ in(B) 2 Na⁺ out / 2 K⁺ in(C) 2 Na⁺ out / 3 K⁺ in(D) 3 Na⁺ out / 3 K⁺ in