This organelle is called C. Plasma or cell membrane.
What is the rest of the question
Cells with large numbers of mitochondria have a high energy demand
In order to create a hydroelectric power plant, you need water, hence the prefix hydro-. Most times, people use dams to block the water, which in a way stores it. When you need to produce electricity, you release some of the water which flows through a turbine making it spin, which then activates a generator to produce electricity.
