Security plays an essential role in the Cisco Collaboration Architecture .In which layers of the Cisco Collaboration Architecture is security implemented?

A.
Cisco security solutions are integrated into the infrastructure layer and partially into the collaboration services layer.

B.
Cisco provides advanced security solutions in the infrastructure and collaboration service layer while the collaboration applications layer security is ensured by third-party solutions.

C.
Security is implemented in all the layers except in the medianet services interface layer.

D.
Advanced Cisco security solutions are implemented in all layers of the Cisco Collaboration Architecture model.