Thelistener is used when the connection is established. The immediate impact of stopping the listener will be that no new session can be established from a remote host. Existing sessions are not compromised.

A: ASM_POWER_LIMIT specifies the maximum power on an Automatic Storage Management instance for disk rebalancing. The higher the limit, the faster rebalancing will complete. Lower values will take longer, but consume fewer processing and I/O resources.
D:
*Normally a separate process is fired up to do that rebalance. This will take a certain amount of time. If you want it to happen faster, fire up more processes. You tell ASM it can add more processes by increasing the rebalance power.
*ASMB ASM Background Process Communicates with the ASM instance, managing storage and providing statistics
Incorrect:
Not B: A higher, not a lower, value of DISK_REPAIR_TIME would be helpful here.
Not E: If you implement database writer I/O slaves by setting the DBWR_IO_SLAVES parameter,
you configure a single (master) DBWR process that has slave processes that are subservient to it.
In addition, I/O slaves can be used to "simulate" asynchronous I/O on platforms that do not
support asynchronous I/O or implement it inefficiently. Database I/O slaves provide non-blocking, asynchronous requests to simulate asynchronous I/O.

If you run multiple AUDIT statements on the same unified audit policy but specify different EXCEPT users, then Oracle Database uses the last exception user list, not any of the users from the preceding lists. This means the effect of the earlier AUDIT POLICY ... EXCEPT statements are overridden by the latest AUDIT POLICY ... EXCEPT statement.
Note:
*The ORA_DATABASE_PARAMETER policy audits commonly used Oracle Database parameter settings. By default, this policy is not enabled.
*You can use the keyword ALL to audit all actions. The following example shows how to audit all actions on the HR.EMPLOYEES table, except actions by user pmulligan.
Example Auditing All Actions on a Table
CREATE AUDIT POLICY all_actions_on_hr_emp_pol ACTIONS ALL ON HR.EMPLOYEES;
AUDIT POLICY all_actions_on_hr_emp_pol EXCEPT pmulligan;
Reference: Oracle Database Security Guide 12c, About Enabling Unified Audit Policies

Explanation/Reference:
Explanation:
Backing Up a Whole CDB
Backing up a whole CDB is similar to backing up a non-CDB. When you back up a whole CDB, RMAN backs up the root, all the PDBs, and the archived redo logs. You can then recover either the whole CDB, the root only, or one or more PDBs from the CDB backup.
Note:
* You can back up and recover a whole CDB, the root only, or one or more PDBs.
* Backing Up Archived Redo Logs with RMAN
Archived redo logs are the key to successful media recovery. Back them up regularly. You can back up logs with BACKUP ARCHIVELOG, or back up logs while backing up datafiles and control files by specifying BACKUP ... PLUS ARCHIVELOG.