单项选择题Fromtheinformationbelow,whatcommandwouldtheadministratorruntoallocatethefilebackedopticaldevice,nameduseful_scripts,tovirtualSCSIadaptervhost0?()
A. mkvdev -dev useful_scripts -vadapter vhost0; loadopt -vdev vtopt0
B. mkvdev -optical useful_scripts -vadapter vhost0; loadopt -vdev vtopt0
C. mkvdev -fbo -vadapter vhost0; loadopt -disk useful_scripts -vtd vtopt0
D. mkvdev -type fbo -vadapter vhost0; loadopt -fbo useful_scripts -vtd vtopt0