Answer : 1. "Laser"
Explanation :

Answer: A) Laser Explanation: Compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony and released in 1982.  These are actually made to replace floppy disks that were used to store files and programs from the computer.   The format was originally developed to store and play only sound recordings but was later adapted for storage of data (CD-ROM).   These CD's uses Laser technology.