The electrons used in the light dependent process comes from: oxygen, water, carbon dioxide or glucose

The light-dependent reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH. In plants, the light reactions take place in the thylakoid membranes of organelles called chloroplasts.

The Calvin cycle is the term used for the reactions of photosynthesis that use the energy stored by the light-dependent reactions to form glucose and other carbohydrate molecules. Hope this helps

b. read the phase at the intersection of any given temperature and pressure.

it's not c. i took the quiz and got it wrong. so my best guess is b.

have a great day, and hope this .