Answer:
Carbondioxide is a reactant of photosynthesis.
Step-by-step explanation:
Carbondioxide is a reactant of the process of photosynthesis and the product of photosynthesis is oxygen, if there is no or less carbondioxide the rate of photosynthesis decreases which leads to the lower production of oxygen. The rate of photosynthesis affected by the reactants available to it. If Carbondioxide is available in large amount more photosynthesis occurs that leads to more production of glucose as well as oxygen. So we can conclude that lack of Carbondioxide results in lower production of oxygen in the process of photosynthesis.