1. cierra
2. empiezan
3. endentemos
4. entiendes
5. prefiere
6. pienso
7. quieren
B. Fueron
Fui is speaking in terms to yourself
Fueron is the best choice because you are talking about what your grandparents did or were they went, in this case you can almost assume the grandparents were doctors there for B. Is the appropriate response.
I think it is goodbye... hope this helps