Which of the following is used as a light source in optical fiber communication1 pointPhotodiodePhototransistorLED and LASERPhotodetector

In optical fiber communication, LED (Light Emitting Diode) and LASER (Light Amplification by Stimulated Emission of Radiation) are used as light sources.

Here's why:

1. LED and LASER are both capable of emitting light when activated. They can convert electrical energy into light energy. This light energy is then used to transmit data over optical fibers.

2. Photodiodes and photodetectors, on the other hand, are used to receive this light at the other end of the communication. They convert the light energy back into electrical signals which can be understood by electronic devices.

3. Phototransistors also work as receivers in optical fiber communication. They amplify the incoming light signal into an electrical signal.

So, the correct answer is LED and LASER.