The following description about ODUk ring network protection, which is wrong?

The following description about ODUk ring network protection, which is wrong?
A . ODUk ring network protection is mainly used in ring networking with distributed services. By occupying two different ODUk channels, it can protect multiple distributed services between all sites.
B . The protection configuration of each site on the ring network must be completed before starting the agreement.
C . Enhanced ODUk ring network protection, no need to set up management nodes. If the management node is set, it will not affect the protection
D . Ordinary ODUk ring network protection does not require a management node.

Answer: D