Refer to the Figure

Refer to the figure.
According to the figure shown, which statement is the most accurate?

A) O₂ concentrations of arterial blood are inversely proportional to swimming speed.
B) As O₂ concentrations of blood drop in venous blood, swimming speed increases.
C) Cold-acclimated fish have a much lower saturation level during exercise than other fish do.
D) As swimming speed increases, the arterial blood remains nearly saturated while the venous blood decreases in saturation.