The atmosphere and the hydrosphere are important parts of the oxygen cycle. Put the tiles in order to show the flow of oxygen through these spheres, starting with the absorption of carbon dioxide by plants. Which of the following options correctly represents the flow of oxygen through these spheres?
1) Photosynthesis releases oxygen into the atmosphere, combustion releases carbon dioxide into the atmosphere, respiration takes place, keeping animals alive, fossil fuels form, living organisms start to decompose.
2) Combustion releases carbon dioxide into the atmosphere, respiration takes place, keeping animals alive, fossil fuels form, living organisms start to decompose, photosynthesis releases oxygen into the atmosphere.
3) Living organisms start to decompose, photosynthesis releases oxygen into the atmosphere, combustion releases carbon dioxide into the atmosphere, respiration takes place, keeping animals alive, fossil fuels form.
4) Fossil fuels form, living organisms start to decompose, photosynthesis releases oxygen into the atmosphere, combustion releases carbon dioxide into the atmosphere, respiration takes place, keeping animals alive.