A system is being booted into maintenance mode due to root password recovery.  After accessing the root volume group and starting a shell without mounting the file systems， what is the next step？（）  

• A、Delete root’s password from the /etc/security/passwd file.
• B、Use the diag recovery tool option to reset root’s password.
• C、Execute the ’passwd’ command and assign a new passwd to root UId
• D、Mount the / and /usr filesystems on alternative mount points to edit the password file.