Your database runs in NOARCHIVELOG mode， and is backed up every night using RMAN scripts. However， last night your assistant DBA performed a manual operating system backup， instead of running the scripts. Today your database crashed and you now want to use the backups from last night. What do you need todo？（）

A.You need to perform the restore and recover operations manually, because the backup was made manually. 
B.First you need to resynchronize the catalog with the control file, and then you can use RMAN to recover the database. 
C.First you need to add the backup to the catalog using the CATALOG command, and then you can use RMAN to recover the database. 
D.You can just use RMAN and recover the database, because RMAN automatically updates the catalog with the backup information.