What is the likely reason that the action failed?

A vSphere administrator needs to increase the capacity of an existing Storage Distributed Resource
Scheduler (SDRS) datastore cluster. The storage administrator has provisioned two new NFS
datastores to be added to the cluster.
The vSphere administrator receives an error message, preventing the administrator from adding the
newly provisioned datastores to the cluster.
What is the likely reason that the action failed?

A.
There are virtual machines running on the datastores being added to the cluster.

B.
The datastores in the SDRS cluster are VMFS datastores.

C.
The datastores in the existing cluster have hardware acceleration enabled and the new datastores
do not.

D.
The SDRS cluster has not been placed into maintenance mode.