A server administrator is notified that all three hard disks in a server array have failed. Which of the following is the MOST likely cause?

An incompatible BIOS would prevent the system from posting or recognizing the RAID controller, but would not physically cause individual hard drives to fail.

The backplane is the shared bus that physically and electrically connects every hard drive to the RAID controller. A backplane failure disrupts the interface for all drives at once, causing them to simultaneously appear as failed or missing to the controller. No other single component would cause every drive in the array to fail at the same time.

A cache battery failure disables write-back caching on the RAID controller, potentially causing a performance degradation or data integrity risk, but does not cause drives themselves to fail.

Incorrect firmware on the controller or drives may cause compatibility or stability errors, but would not simultaneously take all three physical disks offline in the same way a shared hardware failure would.