The correct answer is D. Console.
A console is a hardware device that allows an operator to interact with a computer. It typically consists of a keyboard and a display screen. The keyboard is used to enter commands, and the display screen is used to show the results of those commands.
A card reader is a device that reads data from punched cards. Punched cards were a common way to store data before the advent of magnetic tape and disk storage.
A CPU is the central processing unit of a computer. It is responsible for carrying out the instructions that are stored in the computer’s memory.
A line printer is a device that prints data on paper. Line printers were once a common way to print computer output, but they have been largely replaced by laser printers and inkjet printers.
E is not the correct answer because it is not a unit of hardware.