Which method of call routing would require a user to press the correct line on the phone when making a video call?

A.
Assign at least two different directory numbers on each video-enabled device in the Cisco CallManager cluster, with one line for audio and another line for video. The two lines can then be placed in different partitions and given different calling search spaces.
Assign multiple access codes to both voice and video calls.

B.
Assign at least two different directory numbers on each video-enabled device in the Cisco CallManager cluster, with one line for audio and another line for video. The two lines can then be placed in different partitions and given different calling search spaces.

C.
Assign one directory number to each video-enabled device in the Cisco CallManager cluster, with each line placed in different partitions and given different calling search spaces.

D.
Assign multiple access codes to both voice and video calls.