Would You Expect to Find More Dissolved Oxygen in Polar

Would you expect to find more dissolved oxygen in polar or tropical ocean waters? Why?

A) There would be more dissolved oxygen in the tropical oceans because intense tropical storms mix up the atmospheric oxygen into the ocean water.
B) There would be more dissolved oxygen in the polar oceans because the colder oxygen would "sink" and dissolve into the water.
C) There would be more dissolved oxygen in the tropical oceans because the heated oxygen molecules in the air would collide with and mix into the water.
D) There would be more dissolved oxygen in the polar oceans because the solubility of oxygen in water decreases with increasing temperature.