Question 21

Underwater turbines harness tidal energy.

In this scenario, underwater turbines are utilized to generate electricity from ocean currents, which is a clear indication of tidal energy being harnessed.

A) Tidal

This option is correct as it directly relates to the use of underwater turbines to convert the kinetic energy of ocean currents into electricity. Tidal energy is produced by the movement of water caused by the gravitational pull of the moon and sun, making this the appropriate choice.

B) Geothermal

Geothermal energy is derived from the heat stored beneath the Earth's surface, typically harnessed in volcanic or tectonic regions. It is not applicable in this scenario since the extract discusses ocean currents, not underground heat sources.

C) Wind

Wind energy is generated by converting the kinetic energy from wind into electricity using wind turbines. This option is incorrect as the extract specifies the use of underwater turbines, which are not related to wind energy generation.

D) Biomass

Biomass energy is produced from organic materials, such as plant and animal waste. This option does not relate to the context of generating electricity from ocean currents using underwater turbines, making it an incorrect choice.

Conclusion

The correct answer is A) Tidal, as it accurately describes the energy source utilized in the scenario involving underwater turbines generating electricity from ocean currents. All other options—geothermal, wind, and biomass—fail to align with the extract's focus on ocean currents and their associated energy production.