A.SQL statements that are part of the AWR baseline only 
B.SQL statements based on the AWR top SQL identification
C.SQL statements that are part of the available SQL Tuning Set (STS) only 
D.SQL statements that are available in the cursor cache and executed by a user other than SYS 

A.It improves resync operations when the disk comes online after being taken offline for maintenance purposes. 
B.It improves performance in the extended cluster configuration by reading from a local copy of an extent. 
C.Fewer extent pointers are needed to describe the file and less memory is required to manage the extent maps in the shared pool.
D.This feature enables faster file opens because of the reduction in the amount of memory that is required to store file extents.