Answer:
D. the Calvin-Benson-Bassham pathway
Step-by-step explanation:
The Calvin-Benson-Bassham pathway commonly called the C3 pathway is the sequential step of reactions taking place in the stroma of the chloroplast. The Calvin cycle was studied by the radioactive studies in the green alga by Melvin Calvin.
The Calvin cycle takes place in almost every photosynthetic organism from green algae to green plants. The Calvin cycle is important for the plants as it forms the glucose molecules by the fixation of the carbon from the atmosphere and thus is also known as the Carbon fixation cycle in plants.
Thus, Option-D is correct.