Final answer:
NADPH is produced during the light-dependent reactions of photosynthesis when electrons are passed through an electron transport chain from photosystem I to reduce NADP+ to NADPH.
Step-by-step explanation:
NADPH is made during the light-dependent reactions of photosynthesis, specifically when electrons are transferred through the electron transport chain associated with photosystem I. When photons strike the chlorophyll molecules in photosystem II, they excite electrons, which are then passed down the electron transport chain. This chain culminates with photosystem I, where these electrons are used to reduce NADP+ to NADPH, a process that also involves the capture of a hydrogen ion (H+).
The correct answer to the question 'NADPH is made by' is E. the passing of electrons from photosystem I to an electron transport chain.