Answer:
A. light.
Explanation:
Photosynthesis is the process whereby green plants manufacture their food in form of sugars (glucose) in the presence of sunlight as energy source. The process combines carbon dioxide and water to produce glucose and oxygen, with light source from the sun providing the required energy.
High energy is stored in the bonds of the glucose molecule produced (C6H12O6). This energy emanates from the SUN (solar energy), which the photosynthetic process cannot so without.
