Node Manager is a WebLogic Server （） that enables you to start， shut down， and restart Administration Server and Managed Server from a remote location.

A. Data Grid； Client and Server based
B. Outster； Client and Server based
C. Data Grid；DNS based
D. Cloud cluster；Client and Server based

A. ConcurrentMap
B. java.util.AbstractMap
C. ObservableMap
D. InvocableMap