The correct option is B Dark
Photosynthesis is divided into two sets of reactions: the light-dependent (light) reactions and the light-independent (dark) reactions. The light reactions, which convert the energy in light into chemical energy, take place within the thylakoid membranes of the chloroplasts, whereas the dark reactions, which use that chemical energy to fix CO2 into organic molecules, take place in the stroma of the chloroplast.