The answer that I had think it is c.
The sun--solar energy--is at the heart of the cycle of life, with all the sustenance relationships referred to as the food web. The sun is the ultimate source of energy for animals, but its energy must be harnessed by plants before it can be used by animals. Animals get energy by processing complex foods.
That its not in the cell or that its just there or that you can't find it anywhere else but in the body outside the cell....
