Ah, sorry, I left that part vague. I meant 3 tables, not just two. The point I was trying to make was that your correct answer required junction tables; other interviewers' correct answers require _only_ doctorID, because that's all your text required. And still other interviewers dock points for answering "cleverly" and covering both bases.

Without explicit context, how is the interviewee to know which the interviewer wants? They risk a lower review score no matter how they answer.

Asking the interviewer for more information? The ability to ask questions is far important than whether anyone can remember the details of database normal forms!