IBM Lotus Sametime is being used with Click-to-Call functionality via the Cisco TCSPI plug-in. Which design consideration is the most essential?

A.
The IBM Lotus Sametime Connect client has the TCSPI plug-in installed.

B.
The IBM Lotus Sametime Connect client has the Eclipse plug-in installed.

C.
Telephony is enabled in the default community of the IBM Lotus Sametime server where the TCSPI plug-in is installed.

D.
Telephony is enabled in the default community of the IBM Lotus Sametime server where the Eclipse plug-in is installed.