Which two statements are true regarding Health Monitor checks in Oracle Database 11g?
(Choose two.)
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.
A and B are correct:
https://docs.oracle.com/cd/B28359_01/server.111/b28310/diag007.htm
For A: Redo Integrity Check—This check scans the contents of the redo log for accessibility and corruption, as well as the archive logs, if available. The Redo Integrity Check reports failures such as archive log or redo corruption.
For B: DB Structure Integrity Check—This check verifies the integrity of database files and reports failures if these files are inaccessible, corrupt or inconsistent. If the database is in mount or open mode, this check examines the log files and data files listed in the control file. If the database is in NOMOUNT mode, only the control file is checked.