Which of these are true? ocean zones (50 ! ) a.) i would expect to find equal concentrations of oxygen and carbon dioxide in the epipelagic and the mesopelagic zones because these zones are always well mixed. b.)i would expect to find higher oxygen and lower carbon dioxide concentrations in the epipelagic zone because this is the well-lit zone in which photosynthesis occurs. c.) i would expect to find lower oxygen and higher carbon dioxide concentrations in the epipelagic zone because this is the zone in which the majority of photosynthesis and respiration occurs. d.) i would expect to find lower oxygen and lower carbon dioxide concentrations in the epipelagic zone because this is where the majority of cellular respiration takes place. i think it's b.