From talking to various HR people over the years, nay even actual IT interviewers (people in IT who actually conduct interviews and/or make hiring decision) I've heard something that may or may not be true. They're not always looking for a "right" answer. Sometimes they just want to see how you reason it out, what your thought process is and if you can present some viable solutions.

Very rarely am I in a position where someone says "pick one". It's usually "come up with some options and lets discuss the pros and cons".