Refer to the Exhibit.

What step, it taken, would require all virtual machines in the cluster to migrate automatically?

A.
Deselect the virtual machine from VM Overrides.

B.
Add all virtual machines to the VM Overrides.

C.
Change Response for Host Isolation to Use Cluster Settings.

D.
Change the Automation level to Use Cluster Settings.

Explanation:

After you create a DRS cluster, you can customize the automation level for individual virtual machines to override the cluster’s default automation level.
For example, you can select Manual for specific virtual machines in a cluster with full automation, or Partially
Automated for specific virtual machines in a manual cluster.
If a virtual machine is set to Disabled, vCenter Server does not migrate that virtual machine or provide migration recommendations for it. This is known as pinning the virtual machine to its registered host.
Reference: https://pubs.vmware.com/vsphere-51/index.jsp?topic=%2Fcom.vmware.vsphere.resmgmt.doc%
2FGUID-E83A6B62-37F8-46D0-8D0A-D6A9181979F2.html