Which of the following are input devices?

A. Keyboard
B. Mouse
C. Card reader
D. All of these

Keyboard:

A computer keyboard is an input device that allows a person to enter letters, numbers, and other symbols (these are called characters in a keyboard) into a computer. … Using a keyboard to enter lots of data is called typing. A keyboard contains many mechanical switches or push-buttons called “keys”.

Mouse:

A mouse is a small handheld input device that controls a computer screen’s cursor or pointer in conjunction with the way it is moved on a flat surface.

Card reader:

A card reader is a data input device that reads data from a card-shaped storage medium. … A memory card reader is a device used for communication with a smart card or a memory card. A magnetic card reader is a device used to read magnetic stripe cards, such as credit cards.