Answer:
The answer is C :)
Explanation:
In the first part of photosynthesis (called the light reactions because it only happens when there is sunlight), the energy from the sun is used to split a water molecule (this is where the oxygen comes from).
The high energy electrons from that split water molecule are used to make ATP and to store energy in a molecule called NADPH. Basically, the energy that is stored in these molecules is shuttled over to the Calvin Cycle.
The whole point of the Calvin Cycle is to make carbohydrates (sugars), but this takes a lot of energy. Good thing we have all that energy from the light reactions!!! So, the plant uses the energy to make sugar molecules from carbon dioxide.
If you have any more questions about this process don't hesitate to ask! I'm not sure the level you are learning this material at, so I hope my explanation made sense.
