Answer:
a. True
Step-by-step explanation:
An operating system is a system software pre-installed on a computing device to manage or control software application, computer hardware and user processes.
This ultimately implies that, an operating system acts as an interface or intermediary between the computer end user and the hardware portion of the computer system (computer hardware) in the processing and execution of instructions.
Some examples of an operating system on computers are QNX, Linux, OpenVMS, MacOS, Microsoft windows, IBM, Solaris, VM etc.
In Linux, users are internally represented using a unique number called user ID or UID. Thus, this unique number serves as an internal identifier in the Linux Kernel and as such determines what system resources may be accessible to each user. Oftentimes, these unique numbers are not put into use but rather a name is linked with the number and are used instead.
Also, users can be organized logically into a group and are represented uniquely with a group ID or GID, which serves as a global identifier for the users.