Which of the following is an example of a non-linear load?

A non-linear load is characterized by its ability to draw current in a non-linear manner, often causing distortion in the voltage and current waveforms. LED lights are considered non-linear loads because they do not draw current uniformly throughout the entire AC cycle. Instead, they tend to draw current in pulses due to their electronic components, such as drivers and rectifiers needed for their operation. This pulsing nature can create harmonics and can lead to power quality issues within the electrical system.

In contrast, incandescent light bulbs, electric heaters, and resistive heating elements are examples of linear loads. These devices draw current in a directly proportional manner to the voltage across them, resulting in a smooth and predictable current waveform that does not introduce harmonics into the electrical system. Therefore, LED lights stand out as the non-linear load among the given options due to their unique behavior in current draw.