B (not C): You can validate that all database files and archived redo logs can be backed up by running a command as follows:
RMAN> BACKUP VALIDATE DATABASE ARCHIVELOG ALL;
This form of the command would check for physical corruption. To check for logical corruption, RMAN> BACKUP VALIDATE CHECK LOGICAL DATABASE ARCHIVELOG ALL; D: You can use the VALIDATE keyword of the BACKUP command to do the following:
Check datafiles for physical and logical corruption
Confirm that all database files exist and are in the correct locations.
Note:
You can use the VALIDATE option of the BACKUP command to verify that database files exist and are in the correct locations (D), and have no physical or logical corruptions that would prevent RMAN from creating backups of them. When performing a BACKUP...VALIDATE, RMAN reads the files to be backed up in their entirety, as it would during a real backup. It does not, however, actually produce any backup sets or image copies (Not A, not E).

B: SYSDG administrative privilege has ability to perform Data Guard operations (including startup and shutdown) using Data Guard Broker or dgmgrl.
D: SYSASM
The new (introduced in 11g) SYSASM role to manage the ASM instance, variable extent sizes to reduce shared pool usage, and the ability of an instance to read from a specific disk of a diskgroup E (Not A): SYSDBA is like a role in the sense that it is granted, but SYSDBA is a special built-in privilege to allow the DBA full control over the database Incorrect Answers:
C: SYSKM. SYSKM administrative privilege has ability to perform transparent data encryption wallet operations.
Note:
Use the V$PWFILE_USERS view to see the users who have been granted administrative privileges.

RMAN tablespace point-in-time recovery (TSPITR).
Recovery Manager (RMAN) TSPITR enables quick recovery of one or more tablespaces in a database to an earlier time without affecting the rest of the tablespaces and objects in the database.
Fully Automated (the default)
In this mode, RMAN manages the entire TSPITR process including the auxiliary instance. You specify the tablespaces of the recovery set, an auxiliary destination, the target time, and you allow RMAN to manage all other aspects of TSPITR.
The default mode is recommended unless you specifically need more control over the location of recovery set files after TSPITR, auxiliary set files during TSPITR, channel settings and parameters or some other aspect of your auxiliary instance.

http://gavinsoorma.com/2013/08/oracle-12c-new-feature-in-database-archiving/

Explanation
Explanation:
To perform operations on a single PDB, you can connect as target either to the root or directly to the PDB.
* (A) If you connect to the root, you must use the PLUGGABLE DATABASE syntax in your RMAN commands.
For example, to back up a PDB, you use the BACKUP PLUGGABLE DATABASE command.
* (C)If instead you connect directly to a PDB, you can use the same commands that you would use when connecting to a non-CDB. For example, to back up a PDB, you would use the BACKUP DATABASE command.