Which one of the following is an optical storage device ?

An optical storage device is a data storage medium that uses low-power laser beams to read and write digital data. The technology works by detecting the reflection of laser light off the surface of the disc, which contains microscopic "pits" and "lands" representing binary data.

• CD-ROM (Compact Disc Read-Only Memory) is a primary example of optical storage, along with DVDs and Blu-ray discs.
• Floppy disks, Hard disks, and Magnetic tapes are classified as magnetic storage devices. They use magnetized particles on a rotating disk or moving tape to store information, rather than light-based technology.