Answer:
The correct answer is option C) chemical energy.
Explanation:
In the Calvin cycle or Calvin-Benson cycle ATP adds chemical energy to convert three molecules of CO₂ to one molecule of the 3- carbon sugar. Later in the regeneration stage ATP is again required. In the Calvin-Benson cycle, nine ATPs are converted into nine ADPs, out of which six ATPs are used during the fixation stage and rest three in the regeneration stage.