What safety precaution should always be taken before servicing an appliance?

The correct choice is to disconnect the power supply to the appliance before servicing it. This is a fundamental safety measure that helps prevent electrical shock, which can be life-threatening. Electrical appliances can retain a charge or have live wires even when they appear to be off, making it crucial to ensure that the power is completely turned off before beginning any maintenance or repair work.

Taking this precaution protects not only the technician but also the integrity of the appliance itself. If the appliance is inadvertently powered up while being serviced, it could lead to further damage to components or create hazardous situations, such as fire or injury.

Other safety precautions, while important, do not provide the same level of immediate risk reduction as disconnecting the power supply. For example, removing all appliances from the kitchen is impractical and unnecessary in many cases and does not directly mitigate electrical hazards. Ensuring the appliance is on a stable surface helps prevent mechanical accidents but offers no protection against electrical risks. Wearing safety goggles and gloves is essential for avoiding physical injuries and other hazards, yet it does not address the fundamental risk of electrical shock.