The raw materials of H2O and CO2 are located there
The correct answer is A. grass
One very specific way that humans caused changes in the atmospheric CO2 levels is the fossil fuels that the humans are burning is causing an increase in the CO2 levels. Other ways humans are doing this is by driving cars, deforestation, and an increased industrialization that releases CO2 into the atmosphere.
Explanation:
Inside the air sacs, oxygen moves across paper-thin walls to tiny blood vessels called capillaries and into your blood. A protein called haemoglobin in the red blood cells then carries the oxygen around your body.