What is the purpose of a systemd mount unit?
A. It is used by the command systemd-mount and allows users to mount partitions to mount points of their choice
B. It is used only to mount network file systems to local mount points. It cannot be used for local media
C. It is created by the command systemd-fstab-generator to integrate entries from /etc/fstab into the system boot process
D. It is used by the command mount when using system to mount and unmount file systems
題解
「systemd mount unit」是「systemd」的其中一項功能，藉由在「/etc/systemd/system」目錄下建立不同的「.mount」設定檔案，檔案名稱可以自訂，來分別設定不同的檔案系統要掛載的方式，就不像傳統「/etc/fstab」那樣把檔案系統的掛載設定通通擠在一起，很難直接利用「/etc/fstab」檔案進行選擇性掛載或是卸載。此外，「.mount」設定檔案也跟「.service」檔案一樣，可以方便地使用「systemctl」指令來進行控制。
因此答案是選項「A」。