Which multicast technology provides for this multicast traffic to be distributed with optimal path selection to the source?

Across a large WAN network, there will be new video traffic being distributed from a single source at any given time however, the video source might originate from different parts of the multicast domain at different times.

Which multicast technology provides for this multicast traffic to be distributed with optimal path selection to the source?
A . Any source Multicast.
B . PIM sparse mode.
C . Bidirectional PI
E . Source Specific Multicast.

Answer: D