Among the given options, Linux is not a web browser.
Firefox, Google Chrome, and Opera are all examples of web browsers.
A web browser is a software application that allows you to access and view websites on the internet. It retrieves web pages from servers, displays them on your computer screen, and allows you to interact with them.
Firefox, Google Chrome, and Opera are all popular web browsers that are used to browse the internet. Linux, on the other hand, is an operating system that is used to run software applications, including web browsers like Firefox and Google Chrome.