I think it is because in the ocean the plankton produces most of the oxygen which is used by aquatic plants and plankton is a primary producer known as autotrops.
The sun. Greenhouse gases absorb heat better. So the more of these gases, the hotter it gets. However, the earth itself is naturally heating, but it goes too fast for live to adjust to the temperatures.
This fish is called a jawless fish because it doesnt have any scales
C6H12O6+6O2--->6CO2+6H2O+energy
Oxygen(O2) is used to break down glucose(C6H12O6) into energy so the answer is b
