What of the Following Statements Are True Regarding /Dev/ When

What of the following statements are true regarding /dev/ when using udev?

A) Entries for all possible devices get created on boot even if those devices are not connected.
B) Additional rules for udev can be created by adding them to /etc/udev/rules.d/.
C) When using udev, it is not possible to create block or character devices in /dev/ using mknod.
D) The /dev/ directory is a filesystem of type tmpfs and is mounted by udev during system startup.
E) The content of /dev/ is stored in /etc/udev/dev and is restored during system startup.