Monitors Don't Need Ink Cartridges

I work in an office supply store that sells computers and computer components. One day, one woman came into the store and told me her monitor wasn't working.

Customer: "I can't see color."

Store Worker: "Did you check the connection from the monitor to the computer?"

Customer: "Yeah. Maybe I just need a new ink cartridge."

Store Worker: "Uh...what do you mean?"

Customer: "Maybe my monitor's out of ink."

Store Worker: No."

Customer: "Oh. Well, maybe my printer has something to do with it. It's a Lexmark."