A. Light Fidelity
B. Laser Fidelity
C. Light Frequency
D. Light Fiber

Solution

A. Light Fidelity

Explanation

LiFi (light fidelity) is a bidirectional wireless system that transmits data via LED or infrared light. It was first unveiled in 2011 and, unlike wifi, which uses radio frequency, LiFi technology only needs a light source with a chip to transmit an internet signal through light waves.