At a site, All Oracle instances are found in ConrolCenter. Some are directly monitored by the Database Agent for Oracle, while are others are monitored via proxy. Domain.com is complaining that ControlCenter is not reporting the SID Down alert when some of the Oracle instances go down, even though the SID Down alert definition is enabled, the “Apply this alert to all applicable DB Instances” has been checked and all the Oracle Agents are up.

Which procedure would you advise them to take?

A.
Change the frequency of the SID Down alert from 5 min to 10 min.

B.
Disable the SID Down alert and use Oracle Enterprise Manager instead.

C.
Set up a Management policy for the SID Down Alert.

D.
Use the “Instance Not Accessible” alert for the instances monitored via proxy.