C) It's the most certain answer as all animals are believed to have arise from aquatic unicellular bodies that multiplied and evolved into complex organisms. Like all forms of live they respired and took some millions of years to evolve into land animals thus consuming CO2 into O2.
The answer is: A.Ultraviolet rays from the Sun converted dissolved carbon dioxide to oxygen.
the more carbon dioxide that people pumped into the atmosphere by burning fossil fuels, the more the oceans would absorb. The ocean would continue to soak up more and more carbon dioxide until global warming heated the ocean enough to slow down ocean circulation.
- During development similar species show similar structures. These may include tails or gills. The presence of these structures provides evidence for common ancestry.
