A Voltage Difference Is Maintained Across the Plasma Membrane

Multiple Choice

A voltage difference is maintained across the plasma membrane. This voltage difference

A) is positive on the inside of the cell relative to the outside.
B) does not require energy to generate and maintain.
C) arises because the sodium-potassium pump pumps 2 Na⁺ in and 3 K⁺ out during one catalytic cycle.
D) arises because the sodium-potassium pump pumps 2 K⁺ in and 3 Na⁺ out during one catalytic cycle.
E) arises from secondary active transport.