Which of the Following Best Describes Sodium Movement in the Proximal

Which of the following best describes sodium movement in the proximal tubule?

A) Sodium is transported across the basolateral membrane by the Na+/K+ pump and across the apical membrane by secondary active transport.
B) Sodium is transported across the apical membrane by the Na+/K+ pump and across the basolateral membrane by secondary active transport.
C) Sodium is transported across the apical membrane by the Na+/K+ pump and across the basolateral membrane by facilitated diffusion.
D) Sodium is transported across the basolateral membrane by the Na+/K+ pump and across the apical membrane by diffusion through sodium channels.
E) Sodium is transported across the apical membrane by the Na+/K+ pump and across the basolateral membrane by diffusion through sodium channels.