The First Step of the Na+/ K+ Pump's Activity Involves

The first step of the Na+/ K+ pump's activity involves the binding of which of the following?

A) 2 K+ to their binding site on the outside of the cell
B) 3 Na+ and 2 K+ to their respective binding sites
C) 2 K+ to their binding site on the inside of the cell
D) 3 Na+ to their binding site on the inside of the cell
E) 3 Na+ to their binding site on the outside of the cell