<h3>A) H2O</h3><h3>Explanation.</h3><h3>Water and light are required for light-dependent reactions. The light-dependent reactions utilize light energy to produce two molecules required for the next step of photosynthesis: the power storehouse molecule ATP and the reduced electron transporter NADPH. In plants, the light reactions take place in the thylakoid membranes of organelles named chloroplasts.</h3>
Firstly sunlight is needed for the chloroplast to get it activated by the photons in solar energy so that light dependent reactions take place. And then the raw materials like minerals,water,sunlight,etc... Are needed for the process photosynthesis.
