Answer:
A). Tidal energy.
Step-by-step explanation:
Tidal energy is described as the kind of renewable energy that is produced through the natural rise and fall of the oceanic tides and currents. It is the form of hydropower that helps in producing useful energy primarily electricity.
In the given example, Karl would be able to produce 'tidal' energy from the swimming pool as the pool is the model of the ocean and therefore, the hydropower obtained from its currents and tides can be used to produce electricity and power the LEDs in his science project. Thus, option A is the correct answer.