A: To run Windows in a VM on a machine, you need a full Windows license for the virtual OS, also known as a FPP (Full Packaged Product). You could purchase Windows 7 Professional for the machine then add it to your SA if you use SA in your organization.
You can't use a VDA license. Those are used to grant rights for a user to access a remote client OS running on a server in VDI environments. You can't use VDA because the Windows client OS you're accessing is local, not remote.