What Is the Responsibility of a Secondary WLC

Multiple Choice

What is the responsibility of a secondary WLC?

A) It enables Layer 2 and Layer 3 roaming between itself and the primary controller.
B) It registers the LAPs if the primary controller fails.
C) It avoids congestion on the primary controller by sharing the registration load on the LAPs.
D) It shares the traffic load of the LAPs with the primary controller.