A、 Health Monitor checks can be used to scan the contents of the redo log and archive logs for accessibility and corruption.

B、 Health Monitor checks can be used to verify the integrity of database files and report failures if these files are inaccessible，corrupt or inconsistent.

C、 Health Monitor checks can be used to verify the contents of dictionary entries for each dictionary object and fix it automatically.

D、 Health Monitor checks are always initiated manually when there is some critical error.