While the Ocean Is a Large Sink for Atmospheric Carbon

While the ocean is a large sink for atmospheric carbon dioxide, there is a limit to how much extra carbon the oceans can take out of the atmosphere, due to:

A) the limit of solubility of ocean water to dissolved gases.
B) warmer water not being able to dissolve as much gas as cooler water.
C) the rising acidity of ocean water.
D) all of these.
E) only (a) and (b)