What should you do before executing the commands to restore and recover the data file in ACCOUNTS_PDB?

Your multitenant container database, CDB1, is running in ARCHIVELOG mode and has two
pluggable databases, HR_PDB and ACCOUNTS_PDB. An RMAN backup exists for the database.
You issue the command to open ACCOUNTS_PDB and find that the USERDATA.DBF data file for
the default permanent tablespace USERDATA belonging to ACCOUNTS_PDB is corrupted.

What should you do before executing the commands to restore and recover the data file in
ACCOUNTS_PDB?

A.
Place CDB1 in the mount stage and then the USERDATA tablespace offline in
ACCOUNTS_PDB.

B.
Place CDB1 in the mount stage and issue the ALTER PLUGGABLE DATABASE accounts_pdb
CLOSE IMMEDIATE command.

C.
Issue the ALTER PLUGGABLE DATABASE accounts_pdb RESTRICTED command.

D.
Take the USERDATA tablespace offline in ACCOUNTS_PDB.

Explanation:
* You can take an online tablespace offline so that it is temporarily unavailable for
general use. The rest of the database remains open and available for users to access data.
Conversely, you can bring an offline tablespace online to make the schema objects within the
tablespace available to database users. The database must be open to alter the availability of a
tablespace.