An input device that uses switch contacts placed under a plastic pad which may be inscribed with symbols is known as

Punched card
Touch pad
Punched paper tape
Magnetic disk E. None of the above

The correct answer is B. Touch pad.

A touch pad is an input device that uses a conductive surface to detect the movement of a user’s finger. It is typically used to control the cursor on a computer screen, but can also be used to select items or enter text.

A punched card is a piece of stiff paper that has been punched with holes to represent data. Punched cards were used as a data storage and input medium for computers and other machines from the 1920s to the 1980s.

Punched paper tape is a long, narrow strip of paper that has been punched with holes to represent data. Punched paper tape was used as a data storage and input medium for computers and other machines from the 1950s to the 1980s.

A magnetic disk is a data storage device that uses a magnetic field to store data. Magnetic disks are typically used in hard drives, floppy disks, and other storage devices.

E is not the correct answer because it is not an input device.