A system administrator has added a new graphics card to the system and rebooted. The system pauses with C31 in the three-digit displays. Which of the following causes could be the reason for the hang?（）

• A、All filesets for CDE have not been loaded. Boot into maintenance mode and load them through SMIT.
• B、There is a missing device driver, incorrect console configuration, or a serial device plugged into native S1 port.
• C、The new graphics adapter card is marked defined, not available. Rum smit cfgmgr (Install/Configure Devices Added After IPL with the INPUT device /directory for software set to none). This will reconfigure all devices by walking the bus.
• D、The LED C31 means that there is a corrupted /dev/hd5. Boot into maintenance mode, fsck /dev/hd5 and then issue the bosboot command.