They use the process known as decomposition- much like the name!
B, the others are not testable under lab conditions.
Explanation:
Storing the food helps them to use it in winter and survive because there is very little sunlight available and so they photosynthesis less. When they have extra food they store it in their seeds and when the seed grows it gets it's food from the plant until the plant is able to photosynthesis and produce its food.
Your answer is wall. A cell wall...
Photosynthesis makes a sugar for the plant, in order for photosynthesis to occur the plant needs carbon dioxide and water, and with the use of the sunlight it produces oxygen and glucose. For respiration you need glucose and oxygen which produces carbon dioxide, water and ATP(energy) for the cell. I hope this helps, I only know the first half of the question.