A SAN needs to undergo disruptive maintenance， which will effect a hosted production system with multiple applications and related volume groups， one of which， datavg， resides on the SAN. There is one spare disk in the system but it is smaller than datavg. How can application outages and risk of corruption be minimized？（）

A. Stop the applications in all data volume groups and shut the system down during the outage period.
B. Stop the applications in datavg，unmount all datavg filesystems，varyoff datavg，and export datavg.
C. Stop the applications in datavg，unmount all datavg filesystems，and reduce datavg by the SAN disks.
D. Use the ’cpvg’ command with the -z option to copy and compress datavg to different physical volumes.