Answer:
ATP is used to reduce CO2 to sugar.
Step-by-step explanation:
The Calvin Benson cycle is a set of chemical reactions that takes place in the chloroplast during photosynthesis.
ATP and NADPH produced by light reactions are used to reduce CO2 to sugar. Carbon enters the cycle as CO2. ATP is the energy source while NADPH is the reducing agent that adds high energy electrons t form sugar.