Which of these is not a job of the operating system

An operating system (OS) is the core system software that manages a computer's hardware and resources, and provides the environment in which other programs can run. Its main duties include security, memory management, and process coordination on the local machine.

Stopping unauthorised users from accessing files that do not belong to them is a security function that the operating system genuinely handles, through user accounts, passwords, and file permissions. Allocating memory to running programs is also a core operating system function, since the OS must decide how much RAM each active program can use and prevent programs from interfering with each other's memory space.

Handling HTTP requests for web pages, however, is not something the operating system does. That task belongs to web server software (such as Apache or Nginx), which listens for requests from web browsers and sends back web page content over the internet. A computer can run an operating system perfectly well without ever hosting or responding to any HTTP request.

Exam tip: when a question lists OS duties alongside an internet-specific task like handling web requests, remember that anything tied specifically to serving websites belongs to web server or network application software, not the operating system itself.