Explain the purpose of RCDs (Residual Current Devices).

RCDs, or Residual Current Devices, are designed specifically to enhance electrical safety by monitoring the flow of electrical current through a circuit. Their primary function is to detect any imbalance between the live (active) and neutral currents. This imbalance can occur when there is a leak of current to earth, which could potentially lead to electric shocks or fire hazards.

When an RCD detects such an imbalance, it acts quickly to disconnect the electrical supply, typically within a fraction of a second. This rapid response significantly reduces the risk of serious injury or fatality from electric shocks, as well as the potential for electrical fires caused by faults in insulation or appliances. Therefore, the purpose of RCDs is critical in protecting both people and property from electrical hazards, making their presence essential in household and commercial electrical installations.

Other options do not define the main role of RCDs accurately. For example, while aesthetics may be a consideration in overall electrical design, it's not a function of RCDs. Enhancing power efficiency is not within the scope of RCDs; instead, they are focused purely on safety. Similarly, RCDs are not limited to high voltage installations; they are applicable in various voltage settings, including residential environments where safety against