Answer:
The answer is "Digestion".
Explanation:
The analogy/example given in the question where the production of electricity in a dam is desribed can be related to the metabolic process of digestion where the food is the piped water that is going through the system and in the process producing the equivalent of electricity in the body which is ATP.
I hope this answer helps.
Your image isn't clear so I couldn't see the proper option but lucky for you I have seen this question before so I will tell you the answer.
The answer is option D (facilitated diffusion).
Glucose it the most common carbohydrate found in living things.
Hope this helped! :D