Answer:
The correct answer is d) Lipids
Step-by-step explanation:
Lipids are fat molecule which contains mainly triglyceride made up by the body when extra energy is consumed. Body store lipids to provide energy to the body when there is no glucose left to provide the energy so it acts as a energy reserve.
It is the most efficient form of energy storage because it can provide more calory of energy per gram than protein and carbohydrate.1 gm of lipid can yield 9 kcal while 1 gm of carbohydrate only yields 4 kcal.
So body can go long(weeks) without food due to the energy provided by stored lipids. Glycogen can only provide energy for one or two days.