I also believe the answer is A.
The process of photosynthesis is commonly written as: 6CO2 + 6H2O → C6H12O6 + 6O2. This means that the reactants, six carbon dioxide molecules and six water molecules, are converted by light energy captured by chlorophyll (implied by the arrow) into a sugar molecule and six oxygen molecules, the products.
You can tell if matter is conserved if the substance changes . If the substance changes then matter has been conserved .
The correct answer is C. One change on Earth's surface can result in changes to other Earth systems.
Statistically, none of the other problems would make sense when looking at the graph, other than question A, which we know is the opposite way around.
Hope this helped!
