B.https://www.mansfieldct.org/Schools/MMS/staff/hand/genNaturalselection06.htm this is where I got my source.
Answer:
The red balls here refers to the hydrogen and black balls refers to carbon.
Answer - B. Kidney function is controlled by the blood's composition and hormones.
Reasoning - Well to start off the kidneys (main) purpose function is to clean your blood which is very Important with blood composition. Second It can also and will excrete it through urine which is pretty much what it does. Oh and also a little bit of hormones.
It should be Ozone, hope that helps.
Trees release CO2 which is Oxygen.
Plants release water vapor through Photosynthesis.