Answer: the capillaries.
<span>The blood capillaries are blood vessels with very small caliber. They form the blood distribution and collection network in cells. They are the communication between branches
originating from the arteries and with the smaller
veins. It is on the walls of the capillaries that occurs <span>the exchange of water, oxygen, CO2,
other nutrients and chemical residues.</span></span>
The answer would be C, The rising of global temperatures, why?
Well, global warming means that the worlds temperature is rising.
So, rising global temperature is solid evidence the world is warming up.
Hope this helped! c:
Plants use carbon dioxide and release oxygen during photosynthesis
