In computer security， AAA stands for authentication， authorization and accounting. Which optionabout the AAA authentication enable default group radius enable command is correct？（）

• A、If the radius server returns an error， the enable password will be used
• B、If the radius server returns a ’failed’ message， the enable password will be used
• C、The command login authentication group will associate the AM authentication to a specifiedinterface
• D、If the group database is unavailable， the radius server will be used