Which one of the following laser types is used in a laser printer?

1. Laser printers use a laser beam to project an image of the page to be printed onto an electrically charged, rotating drum coated with selenium or, more commonly now, organic photoconductors. 2. The type of laser typically used in a laser printer is a Semiconductor laser (also known as a laser diode). 3. These lasers are compact, efficient, and suitable for modulating quickly to create the image pattern on the drum. 4. Dye lasers, Gas lasers (like HeNe or CO2), and Excimer lasers have different characteristics and applications and are not typically used in standard laser printers.