Hi Jim,
Recursive check would be a preference. So in your example, the list should return Group A and Group B, indicating that Group B is member of Group A.
If it is not possible, I may find a workaround and create the parent-child relationship staticly and lookup the structure from there but dynamic recursive check would make the life much more easier.
I see from your signature that you are a programmer in QDABRA, will you start implmenting this or what would be the next steps?
Thank you