Ferredoxins are iron-sulfur proteins that mediate electron transfer in a range of metabolic reactions.

NADP+ accepts and holds 2 high-energy electrons along with a hydrogen ion (H+).

B. photons

Because the question does not ask photosynthesis, I answer in the meaning of general chemistry:

Light just provides energy for a reaction; usually, photons (the light particles) make electrons of the matter to excitate, thus changing the reaction conditions.

Otherwise, in photosynthesis, light-dependent reactions produce a proton (H+) gradient flow through thylakoid membrane, thus spinning the ATPase enzyme subunits, thus producing ATP. Besides this, ferredoxin and NADPH is produced. Ferredoxin is very important for certain specific enzymatic reactions and NADPH is the carrier of reduction force (it can give a hydrogen to a chemical/metabolite, for example to malonic acid)

It is placed as second photosystem in the light reactions of plants, algae and some bacteria. It is an integral membarne protein complex. It functioning the electron transfer from plastocyanin to ferredoxin. Like PSII, PSI also uses light energy to excite electrons.