When upgrading vCenter Server, an administrator notices that the upgrade fails at the vCenter Single Sign-On installation.
What must be done to allow the upgrade to complete?

A.
Verify that the VMware Directory service can stop by manually restarting it.

B.
Verify that the vCenter Single Sign-On service can stop by manually restarting it.

C.
Uninstall vCenter Single Sign-On service.

D.
Uninstall the VMware Directory service.