Which two statements are correct?

You execute the following FLASHBACK TABLE command:
SQL> FLASHBACK TABLE emp TO TIMESTAMP TO_TIMESTAMP(‘2008-01 -04
11:00:00′,’YYYY-MMDD HH24:MI:SS’);
Which two statements are correct? (Choose two.)

A.
The emp table that was dropped by mistake earlier is restored.

B.
The FLASHBACK TABLE statement is executed as a single transaction.

C.
The FLASHBACK TABLE statement does not maintain existing indexes on the emp table.

D.
The changes made to the emp table since the specified time are undone if no constraint
is violated during flashback.

Explanation:
FLASHBACK TABLE (Link)
Purpose
Use the FLASHBACK TABLE statement to restore an earlier state of a table in the event of
human or application error. The time in the past to which the table can be flashed back is
dependent on the amount of undo data in the system. Also, Oracle Database cannot restore
a table to an earlier state across any DDL operations that change the structure of the table.
Semantics

During an Oracle Flashback Table operation, Oracle Database acquires exclusive DML
locks on all the tables specified in the Flashback list. These locks prevent any operations on
the tables while they are reverting to their earlier state.
The Flashback Table operation is executed in a single transaction, regardless of the number
of tables specified in the Flashback list. Either all of the tables revert to the earlier state or
none of them do. If the Flashback Table operation fails on any table, then the entire
statement fails.
At the completion of the Flashback Table operation, the data in table is consistent with table
at the earlier time.
However, FLASHBACK TABLE TO SCN or TIMESTAMP does not preserve rowids, and
FLASHBACK TABLE
TO BEFORE DROP does not recover referential constraints.
Oracle Database does not revert statistics associated with table to their earlier form. Indexes
on table that exist currently are reverted and reflect the state of the table at the Flashback
point. If the index exists now but did not yet exist at the Flashback point, then the database
updates the index to reflect the state of the table at the Flashback point. However, indexes
that were dropped during the interval between the Flashback point and the current time are
not restored.
Logical Flashback Features Useful in Backup and Recovery (Link)
The remaining flashback features operate at the logical level. The logical features
documented in this chapter are as follows:
Flashback Table
You can recover a table or set of tables to a specified point in time in the past without taking
any part of the database offline. In many cases, Flashback Table eliminates the need to
perform more complicated point-in-time recovery operations. Flashback Table restores
tables while automatically maintaining associated attributes such as current indexes, triggers
and constraints, and not requiring you to find and restore application-specific properties.
“Rewinding a Table with Flashback Table” explains how to use this feature.
Flashback Drop
You can reverse the effects of a DROP TABLE statement.
“Rewinding a DROP TABLE Operation with Flashback Drop” explains how to use this
feature.
Note:
Because the logical flashback features have uses not specific to backup and recovery, some
documentation for them is located elsewhere in the documentation set.
All logical flashback features except Flashback Drop rely on undo data. Used primarily for
providing read consistency for SQL queries and rolling back transactions, undo records
contain the information required to reconstruct data as it existed at a past time and examine
the record of changes since that past time.