Your ARCHIVELOG-mode database has lost three datafiles and shut down. One is assigned to the SYSTEM tablespace and two are assigned to the USERS tablespace. You can choose from the following steps to recover your database：  
a. Restore the three database datafiles that were lost. 
b. Issue the Startup Mount command to mount the database. 
c. Issue the alter database open command. 
d. Issue the alter database open resetlogs command. 
e. Recover the database using the recover database command.
f. Recover the datafiles with the recover datafile command. 
g. Take the datafiles offline. 
Which is the correct order of these steps in this case？（）

A. Backup control file.
B. Emergency control file.
C. The create controlfile command.
D. The restore controlfile SQL*Plus command.
E. No backup is required. The database will re-create the control file when it is discovered to be lost.

A. Restore the 19ths backup， restore all archived redo logs， recover the database to the 20th，and open the database.
B. Tell them that their request cannot be met with the current backup strategy.
C. Restore the 19ths backup， apply the online redo logs，and open the database.
D. Switch the database into ARCHIVELOG mode，restore the 19th’s backup，restore all archived redo  logs，and recover the database to the 20th.
E. Use the recover database command to roll back the database from today to the 19th of the month.

A. You will need to open the database with the resetlogs command.
B. All you need to do is execute the trace file from SQL*Plus and it will perform the recovery for you.
C. You will use the resetlogs version of the create controlfile command.
D. You will use the noresetlogs version of the create controlfile command.
E. You will use the trace file to create a backup control file， and then you will recover the database with the recover database using backup controlfile command