What command would you use to check the current runlevel in a Linux system?

The command used to check the current runlevel in a Linux system is indeed the command that directly relates to the traditional SysVinit system, where "runlevel" indicates the state of the system. When executed, this command provides the current runlevel numerically and can be particularly useful for systems that still rely on runlevels to manage their operational state.

While modern systemd-based systems have shifted away from the concept of runlevels in favor of targets, the 'runlevel' command remains valid and is available in those systems for compatibility reasons. It effectively displays the current operational state of the system in a straightforward manner, making it an essential command for administrators familiar with traditional Linux systems.

The other options pertain to the more modern systemd-based approach to managing services and system states. Commands like "systemctl get-default" and "systemctl show runlevel" focus on retrieving the default target or displaying information not specifically tied to the current state of the runlevel but rather the default configurations or settings. Similarly, "init get-default" is not valid since the "init" command is not used in the context of systemd, and even though it pertains to SysVinit, it doesn't directly check the current runlevel.

Thus,