Your database instance is functional for the past one month. The Automatic Workload Repository（AWR） snapshot retention is set to 7 and the STATISTICS_LEVEL initialization parameter is set to TYPICAL. 
You receive a complaint about the poor performance of the database between 7 PM and 9 PM of theprevious day. 
Choose two actions any of which can be referred to first to diagnose the problem. （）

A.The ADDM requires at least four AWR snapshots for analysis.
B.The ADDM runs after each AWR snapshot is collected automatically by MMON.
C.The results of the ADDM analysis are stored in the Automatic Workload Repository （AWR）.
D.The ADDM analysis provides only diagnostic information but does not provide recommendations.
E.The ADDM calls other advisors if required， but does not provide recommendations about the advisors.

A.It transfers statistics from memory to disk at regular intervals.
B.It coordinates the rebalance activity for disk groups when ASM is used.
C.It communicates with the Automatic Storage Management （ASM） instance on behalf of the databaseinstance.
D.It performs dynamic memory management when Automatic Shared Memory Management is enabledfor the database instance.

A.Insert finding directives for ADDM tasks in the future.
B.Create a baseline on a pair of snapshots spanning the peak-load period.
C.Decrease the snapshot interval in the AWR to collect more snapshots during the peak-load period.
D.Set the snapshot retention period in the Automatic Workload Repository （AWR） to zero to avoid automatic purging of snapshots.