It is c.a decrease of gravity!!
The answer to this question should be: Calvin cycle
Calvin cycle is a chemical reaction that was done in the chloroplast of a plant. This is one of the reactions in photosynthesis. In Calvin cycle, carbon dioxide and water will be used to make carbohydrates(glucose). This reaction is forming energy using the sunlight so only autotrophic organism capable that will be able to do it.
Delta can also be an easy answer plus it is easy to remember
6CO2 + 6H20 + (energy) → C6H12O6 + 6O2
Carbon dioxide + water + energy from light produces glucose and oxygen.
