The purpose of the LED indicator is to

A) aid in fault diagnosis.
B) set the minimum level of voltage that can be detected.
C) protect against electrical noise interference.
D) separate the higher line voltage from the logic circuits.

LED Indicator

A light-emitting diode used as a visual signal to represent the status or condition of a device, operation, or process.

Electrical Noise Interference

Unwanted disturbances superimposed on a useful signal that tend to obscure its information content, often caused by electromagnetic disturbances.

Logic Circuits

Electronic circuits that implement logical functions, they are the building blocks of digital devices, able to process binary data input into specific outputs.