What are OS programs that run in the background and are usually started during the OS initialization process?

The correct answer is services. In an operating system, services are programs that operate in the background to provide essential functionality and support for various system and application processes. They are typically started automatically when the operating system initializes, allowing them to run continuously without user intervention. This ensures that key system functions, such as network management, hardware communication, and scheduled tasks, are always available, enabling other applications and users to operate smoothly.

In contrast, while shells are command-line interfaces used to interact with the operating system, they do not run in the background during system startup. Drivers are specific programs that allow the OS to communicate with hardware devices but are not considered services in the traditional sense. Utility software refers to specialized applications designed for maintenance and optimization tasks rather than foundational services that support the system's core functionality.