When someone asks you, “What are the three essential….?” in an interview, reply, “There’s really only one, and here’s what it is….”
Don’t confine yourself to an interviewer’s lazy questioning, and don’t feel defensive in having to come up with three answers. You’re the expert. A good interviewer should ask, “What are the most important….?”
Most interviewers haven’t done their homework well, so I just take over the interview and lead it in the right direction.