An Electrogenic Na⁺ Transporter

An electrogenic Na⁺ transporter:

A) catalyzes facilitated diffusion of Na⁺ from a region of high Na⁺ concentration to one of lower Na⁺ concentration.
B) must catalyze an electron transfer (oxidation-reduction) reaction simultaneously with Na⁺ transport.
C) must transport both Na⁺ and a counterion (Cl^-, for example) .
D) transports Na⁺ against its concentration gradient.
E) transports Na⁺ without concurrent transport of any other charged species.