When using InfoSphere Federation Server to access Optim extended data sources, what must be created to define a federated object?

A.
A wrapper, a system definition, a user mapping, and a nickname

B.
A wrapper, a server definition, a user mapping, and a DB Alias

C.
A wrapper, a system definition, a nickname, and a DB Alias

D.
A wrapper, a server definition, a user mapping, and a nickname