Which of the following options for the kernel's command line changes the systemd boot target to rescue.target instead of the default target?

systemd.target= is not a valid systemd kernel parameter; the correct parameter name is systemd.unit=, not systemd.target=.

systemd.runlevel= is not a recognized systemd kernel parameter; runlevels are a SysV concept and systemd does not use this parameter name for target selection.

systemd.service= is not a valid kernel parameter for changing the boot target; it does not exist as a standard systemd kernel command line option.

systemd.default= is not a valid systemd kernel parameter; no such option exists in the systemd kernel command line interface.

systemd recognizes the kernel parameter systemd.unit= to specify which unit file to use as the initial target instead of the compiled-in default (usually multi-user.target or graphical.target). Setting systemd.unit=rescue.target at the bootloader prompt boots the system into rescue mode, providing a minimal single-user environment for recovery tasks.