What additional configuration on the Cisco switches is recommended for high availability and redundancy?

The ECS network solution for an organization is designed to have 4x10GbE uplinks connected to both Cisco switches. The organization will create the needed port channels.

What additional configuration on the Cisco switches is recommended for high availability and redundancy?
A . Ring topology
B . Dedicated VLANs
C . Spanning tree protocol
D . Virtual port channel

Answer: D