The Calvin cycle includes three main phases namely, carbon fixation, reduction, and regeneration of carbon acceptor. Which one of the following options correctly describes all these three phases?

• A. ATP is utilized in all phases
• B. ATP is utilized in both the reduction and regeneration phases, while NADPH is utilized in the reduction phase only
• C. Carbon dioxide is utilized only during the reduction phase
• D. The reduction phase is the first phase of the Calvin cycle

Answer: (B)