An administrator suspects problems on a SCSI hard disk， but upon running diagnostics， no errors were found. What must be done to check the condition of the drive？（）
A、Run diag and select the ’Certify Media’ task.
B、Perform a read and write test on the disk and monitor errorlog.
C、Update the disk firmware to the latest level and monitor errorlog.
D、Format the disk to ensure bad blocks are omitted from the disk layout.
