The right answer is A.
Respiration is the opposite of photosynthesis: it consumes O2 and glucose and releases CO2 by releasing chemical energy, while photosynthesis uses glucose and CO2 and releases O2, using light energy. They are therefore symmetrical mechanisms: they involve electron fluxes within their membrane and lead to the production of molecules rich in energy. In addition, the organelles responsible for these reactions (chloroplasts and mitochondria) have many points in common, as well as their bacterial origin. Both allow the formation of ATP, a universal energetic molecule of the living.
