Which method must a network engineer use to upgrade the BIOS firmware or a Cisco UCS standalone C-Series rack-mount server?

Which method must a network engineer use to upgrade the BIOS firmware or a Cisco UCS standalone C-Series rack-mount server?

A. Use the U-ACPI Interface. B. Use the Cisco host upgrade utility. C. Use the Cisco hardware upgrade utility. D. Use the Cisco host firmware policy.