Answer:
The correct option is D) oxygen
Step-by-step explanation:
The splitting of the water molecules during the light-dependent reactions results in the production of 2 electrons, two hydrogen ions and the formation of oxygen gas. The electrons released by this process make ATP by a process which is known as chemiosmosis. The hydrogen ions released during the light-dependent reactions are converted into NADPH during the light-independent reactions. Oxygen is the by-product and is released into the air. The oxygen is used up by other organisms of the earth for cellular respiration.