Which command CANNOT be used to mount a shared filesystem in your Linux environment?

A.
mount.cifs //server/share /mnt -o user=user

B.
mount -t cifs //server/share /mnt -o user=user

C.
mount -t smbfs //server/share /mnt -o username=user

D.
smbmount //server/share /mnt -o username=user

E.
cifsmount //server/share /mnt -o username=user