A.Shut down the database, restore the two data files and then start up the database.
B.Take the system and users tablespace offline, restore the two data files, recover the two datafiles, and then bring the SYSTEM and USERS tablespaces online.
C.Shut down the database, restore the two data files, start up the database in MOUNT mode, recover the two data files, and then alter the database open.
D.Take the SYSTEM and USERS tablespaces offline, recover the two datafiles and then bring the SYSTEM and USERS tablespaces online.