Which is not a main function of an operating system? A. Running applications B. Playing games C. Printing documents

To determine which option is not a main function of an operating system, let's analyze the choices:

1. Running applications: This is a core function of an operating system. It manages the execution of applications and provides the environment necessary for them to run effectively.

2. Playing games: While many users play games on their computers, playing games is not a fundamental function of an operating system. Instead, the OS provides the necessary resources and management for applications, which may include games, but does not specifically focus on gaming.

3. Printing documents: This is another essential function of an operating system. It manages the hardware and software resources involved in printing, allowing users to print documents as needed.

Conclusion

The answer is B. Playing games, as it is not a main function of an operating system but rather a result of the environment and applications that the OS supports.