Correct option is D
1.
Wi-Fi:
· Incorrect. Wi-Fi is a wireless communication technology for connecting devices to a network but is not a storage device.
2.
Modem:
· Incorrect. A modem is a device that modulates and demodulates signals for internet communication but does not store information.
3.
POP (Post Office Protocol):
· Incorrect. POP is a protocol used for retrieving emails from a mail server and does not refer to physical storage.
4.
Hard Disk:
·
Correct. A hard disk is the primary storage device in a computer where data, files, and programs are physically stored.
