Question

the diagram summarizes the light - dependent reactions of photosynthesis. what is the input of the light - dependent reactions, labeled x? co₂, h₂o, o₂, and light co₂, h₂o, and light co₂ and h₂o h₂o and light

Explanation:

In the light - dependent reactions of photosynthesis, water ($H_2O$) is split and light energy is used to produce chemical energy (ATP and NADPH) and release oxygen. Carbon dioxide ($CO_2$) is used in the light - independent reactions (Calvin cycle), not in the light - dependent reactions. Oxygen ($O_2$) is an output, not an input. So the inputs are water and light.

Answer:

D. $H_2O$ and light