Explanation/Reference:
Explanation:
D: An unplugged PDB contains data dictionary tables, and some of the columns in these encode information in an endianness-sensitive way. There is no supported way to handle the conversion of such columns automatically. This means, quite simply, that an unplugged PDB cannot be moved across an endianness difference.
E (not F): To exploit the new unplug/plug paradigm for patching the Oracle version most effectively, the source and destination CDBs should share a filesystem so that the PDB's datafiles can remain in place.
The PDB must be closed before it can be unplugged. When you unplug a PDB from a CDB, the unplugged PDB is in mounted mode. The unplug operation makes some changes in the PDB's data files to record, for example, that the PDB was successfully unplugged. Because it is still part of the CDB, the unplugged PDB is included in an RMAN backup of the entire CDB. Such a backup provides a convenient way to archive the unplugged PDB in case it is needed in the future.

Explanation/Reference:
Explanation:
A: You can create and rebuild indexes online. Therefore, you can update base tables at the same time you are building or rebuilding indexes on that table. You can perform DML operations while the index build is taking place, but DDL operations are not allowed. Parallel execution is not supported when creating or rebuilding an index online.
D: Moving (Rebuilding) Index-Organized Tables Because index-organized tables are primarily stored in a B-tree index, you can encounter fragmentation as a consequence of incremental updates. However, you can use the ALTER TABLE...MOVE statement to rebuild the index and reduce this fragmentation.
C: If a table can be compressed in the new tablespace, also it can be compressed in the same tablespace.
Incorrect Answers:
B, E: Local and Global indexes can be automatically rebuild with UPDATE INDEXES when you move the table.
References: http://www.oracle.com/technetwork/issue-archive/2014/14-may/o34dba-2193424.html

1.Ensure that the exporting user at the source database has the DATAPUMP_EXP_FULL_DATABASE role. This user must be specified when you create the database link.
2.Ensure that the importing user at the destination database has the DATAPUMP_IMP_FULL_DATABASE role.
3.Create and test a database link between the source and destination databases.
4.Run the following command, where import_user is the username for the importing user, and db_link is the name of the data base link owned by the exporting user: IMPDP import_user NETWORK_LINK=db_link FULL=Y;

E: By default, flashback archiving is disabled for any table. You can enable flashback archiving for a table if you have the FLASHBACK ARCHIVE object privilege on the Flashback Data Archive that you want to use for that table.
D: Creating a Flashback Data Archive
/ Create a Flashback Data Archive with the CREATE FLASHBACK ARCHIVE statement, specifying the following:
Name of the Flashback Data Archive
Name of the first tablespace of the Flashback Data Archive (Optional) Maximum amount of space that the Flashback Data Archive can use in the first tablespace
/ Create a Flashback Data Archive named fla2 that uses tablespace tbs2, whose data will be retained for two years:
CREATE FLASHBACK ARCHIVE fla2 TABLESPACE tbs2 RETENTION 2 YEAR;

Explanation/Reference:
Explanation:
A: Setting a PDB resource plan is optional. If not specified, all sessions within the PDB are treated equally.
* In a non-CDB database, workloads within a database are managed with resource plans.
In a PDB, workloads are also managed with resource plans, also called PDB resource plans.
The functionality is similar except for the following differences:
/Non-CDB Database
Multi-level resource plans
Up to 32 consumer groups
Subplans
/PDB Database
Single-level resource plans only
Up to 8 consumer groups
(not B) No subplans