A light sensitive device that converts drawing, printed text or other images into digital form is

An input device is described here as being light sensitive and able to convert physical images such as drawings, printed text, or photographs into a digital form the computer can store and process. This describes a scanner.

A scanner works by passing a light source and photosensitive sensor over the surface of a document or image, the sensor detects variations in reflected light and converts them into digital pixel data, which the computer can then display, edit, or store as an image file.

A keyboard converts key presses into text, it does not read images, a plotter is an output device that draws graphics onto paper rather than reading them in, and an OMR (Optical Mark Reader) only detects the presence of marks in predefined positions, such as on multiple-choice answer sheets, it cannot capture a full image or block of printed text the way a scanner does.

Exam tip: when a question mentions converting a printed image, drawing, or document into digital form, think scanner, when it mentions detecting pre-marked positions like shaded ovals, think OMR.