A cloud architect created a new delivery controller for a large VM farm to scale up according to organizational needs. The old and new delivery controllers now form a cluster. However, the new delivery controller returns an error when entering the license code. Which of the following is the MOST likely cause? 

Answer options:

A. A firewall is blocking the port on the license server.
B. The existing license is for a lower version.
C. The existing license is not supported for clusters.
D. The existing license has expired.

C

Can`t be a firewall issue, or the old delivery controller would have a license error as well. Based on the information given, I would say they are not licensed for clustering.