Which command would you use to check the run level of the system?

The command used to check the run level of a Linux system is runlevel. This command provides information about the current run level, which is a state of the system indicating what services and processes should be running. Each run level corresponds to a specific mode of operation for the operating system, such as multi-user mode, graphical mode, or single-user mode.

When executed, the runlevel command will return the current run level of the system along with the previous run level, if applicable. This is useful for system administrators who need to understand which services are operating based on the defined run levels.

The other options do not correspond to valid commands used in Linux for this purpose. They either do not exist in standard distributions or do not perform the function described regarding run levels. Understanding how to check and manage run levels is a fundamental skill for Linux system administration.