I'd go with the third one because the products of both of them are oxygen and carbon dioxide.
The acceleration would be the velocity at point O divided by the time of point O, also known as the slope at point O. (y/x)
It is produced by transformed bacteria.
True, because if the world gets warmer, glaciers will melt, causing there to be more available water. If the world gets cooler, glaciers will form, causing there to be less available water.
B. Scientific theory
A scientific theory is an explanation supported by scientific evidence. How ever many times you test it, you will get the same result.
I hope that helps! :)