In which layer of the Cisco Collaboration Architecture would you find session and content management

In which layer of the Cisco Collaboration Architecture would you find session and content management?

A.
endpoint device layer

B.
collaboration applications layer

C.
infrastructure layer

D.
collaboration services layer

Explanation:

http://www.cisco.com/en/US/solutions/collateral/ns340/ns858/c22-613680_sOview.html