Being stuck with a lack of free disk space in my Windows 10 VM running on VMWare workstation 12.0, with the need to move on with a Win10 build upgrade, I found the solution by using the EaseUS partition Manager free version.
https://www.easeus.com/partition-manager/epm-free.html
With drag&drop, once I could expand the VM by 5GB, then PartitionManager let me easily move the DataRecovery partition to the end of the newly allocated space, then merge the old C partition with the new space.