Assume your situation can be described as follows：
x A full backup taken using RMAN is available on disk. 
x The current control files were NOT damaged and do not need to be restored. 
x All data files are damaged or lost. 
x The database is in NOARCHIVELOG mode. 
Which RMAN command would be most appropriate to use in line 3 of the following RMAN command set to restore and fully recover your database？（）
1. RMAN> STARTUP MOUNT 
2. RMAN> RESTORE DATABASE; 
3. RMAN> （） 
4. RMAN> ALTER DATABASE OPEN; 

A.RECOVER DATABASE；
B.SWITCH DATAFILE ALL；
C.RESTORE CONTROL FILE；
D.RECOVER DATABASE USING BACKUP CONTROL FILE；