Correct option is D
A
hard disk is a data storage device used to store and retrieve digital information using one or more rigid rapidly rotating platters coated with magnetic material.
It is the
physical place where a computer stores operating system files, software, documents, and other data.
Now-a-days hard disk occurs in two variants i.e. internal & external hard disk. Internal hard disk occurs as a part of same system while external may be used through all computers with the help of a connector.
MODEM— A modulator-demodulator or modem is a computer hardware device that connects a computer or router to a broadband network e.g. Cable Modem, DSL
Modem etc.
WiFi— is a wireless technology used to connect computers, tablets, smart phones and other devices to the internet.
POP—Point-of-presence (POP) is an access point from one place to the rest of the Internet.
