Question: what are the three reactants used in photosynthesis?
Answer: In photosynthesis, oxygen, carbon dioxide, ATP, and NADPH are reactants. ...  In photosynthesis, chlorophyll, water, and carbon dioxide are reactants. ...  In photosynthesis, water, carbon dioxide, ATP, and NADPH are reactants. ...  In photosynthesis, water and carbon dioxide are reactants.