A machine is running in single user mode and, as such, not all file-systems are accessible. What
command must be run to make all of the other file-systems listed in /etc/fstab accessible?

A.
mount –all

B.
mountfs –all

C.
mountfs -a

D.
mount -a

Explanation:
From the man pages:
Mount – mount a filesystem
-a, –all Mount all filesystems (of the given types) mentioned in fstab.