Which of the following commands reboots the system when using SysV init? (Choose TWO correct answers.)

shutdown -r now sends a reboot signal immediately; it notifies logged-in users, cleanly terminates processes, unmounts filesystems, and then instructs SysV init to reboot the system.

shutdown -r requires a time argument before the message string; 'shutdown -r "rebooting"' passes the quoted string as the time argument, which is invalid and will cause an error.

In SysV init, runlevel 6 is defined as reboot; telinit 6 instructs the init process to transition to that runlevel, triggering a clean system reboot.

telinit 0 transitions the system to runlevel 0, which is halt or poweroff - not a reboot.

The -k flag tells shutdown to send warning messages to logged-in users but explicitly does NOT perform any shutdown or reboot action.