Correct option is C
An opto-coupler (or opto-isolator) is a device that provides electrical isolation between the input and output circuits. It does this by using light as the medium for signal transfer.
· The input side contains an
LED that emits light proportional to the input signal.
· The output side contains a
photodetector (photodiode, phototransistor, etc.) that receives the light and generates a corresponding electrical signal.
