Erasing and reinstalling macOS deletes user accounts, files, and network settings from the Mac. Apple therefore recommends backing up any files that must be preserved and recording the current network configuration before the erase begins. This makes option D correct. Startup Disk does not provide a feature for exporting a network-settings profile, and Setup Assistant cannot recover settings that were not backed up or otherwise preserved. There is also no standard macOS restore option named “Preserve all data” when the startup volume is being erased. Recording details such as Wi-Fi, Ethernet, DNS, proxy, or other required network information makes it easier to reconnect after macOS is reinstalled. A current data backup protects the user’s files, while the written network settings preserve configuration information that the erase would otherwise remove.

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