Companycom wants to apply a PTF to the p5 590 system. After doing a preview install, the output shows there is insufficient space in the /usr filesystem. The root volume group has no available physical partitions left. They do not want to add additional disk drives to the system, but have a jfs2 filesystem that is only 8% used. What could they do to utilize space in the jfs2 filesystem to apply this PTF?（）
- ABackup the filesystem and recreate smaller
- BUse the chfs to reduce the filesystem size
- CUse cplv to copy filesystem to smaller size
- DUse migratepv to copy filesystem to smaller size