Which of the following statements are true about Compact Disc (CD) and Digital Versatile Disk (DVD)? Each correct answer represents a complete solution. Choose all that apply.

CDs and DVDs store data optically rather than magnetically or electronically, so an electromagnetic pulse (EMP) from a nuclear detonation does not directly corrupt the encoded pits and lands, unlike magnetic hard drives or flash memory.

CD and DVD data is physically encoded as microscopic pits and lands (flat areas) on the disc surface, which a laser reads by detecting differences in light reflection - this is the fundamental optical storage mechanism for both formats.

CDs and DVDs are not immune to all electromagnetic radiation - strong X-rays, ultraviolet radiation, and intense heat can degrade the dye layer or polycarbonate disc substrate and cause permanent data loss.

The reflective dye layer and polycarbonate substrate of CDs and DVDs can be degraded by relatively small amounts of energy such as heat, UV light, or physical scratching, making data corruption possible without requiring large energy levels.