Should be E: In the GRUB menu, choose the first entry and press "e" to edit it Hit the DOWN arrow and find the line that starts with the word "linux" and add the following line at the end of it. To reach the end, just press CTRL+e or use the END key or LEFT/RIGHT arrows in your keyboard. systemd.unit=rescue.target

Option D. systemd.default=rescue.target is the option that changes the systemd boot target to rescue.target instead of the default target. Systemd is a system and service manager that is used in many Linux distributions as the init system. It organizes services and daemons into units and groups them into boot targets, which determine the set of units that are activated at boot time. The default boot target is the one that is activated by default when the system boots. To change the systemd boot target, you can use the systemd.default kernel parameter on the kernel's command line. For example: systemd.default=rescue.target This will change the boot target to rescue.target, which activates a minimal set of units that are required to provide a rescue shell and access to emergency tools. Option E: The systemd.unit kernel parameter does not exist. It is not a valid option for changing the systemd boot target. Options A, B, and C are also incorrect. They are not valid options for changing the systemd boot target.

Correct E https://www.thegeekdiary.com/how-to-boot-into-rescue-mode-or-emergency-mode-through-systemd-in-centos-rhel-7-and-8/

Answer is correct