You have been recently hired as a database administrator. Your senior manager asks you to study the production database server and submit a report on the settings done by the previous DB 
A. While observing the server settings， you find that the 
following parameter has been set in the parameter file of the database： REMOTE_OS_AUTHENT = TRUE 
What could have been the reason to set this parameter as TRUE？（）

A.SQL*Plus
B.iSQL*Plus
C.Management Server
D.Management Repository
E.Oracle Enterprise Manager 10g Database Control

A.On startup， SMON coordinates instance recovery.
B.On startup， CKPT coordinates instance recovery.
C.On startup， use RMAN to perform instance recovery.
D.Uncommitted changes will be rolled back after the database is opened.
E.On startup， perform media recovery and then instance recovery.
F.On startup， all the files will be synchronized and you get both committed and uncommitted data.

A.uses undo data for roll forward
B.uses Flashback Log for recovery
C.uses online redo logs to roll back
D.uses undo data to roll back the transaction
E.uses Recovery Manager （RMAN） to roll back
F.uses the System Monitor （SMON） background process to perform instance recovery