In general, “scoring” during an interview depends on more than simply having an answer ready for every question. Interviewers are interested in your attitude and maturity, your work ethic, your professionalism and how well you communicate. Regardless of the job, they’re also evaluating you as a problem solver, a team player and someone who wants to learn and grow.
When you get an unexpected question, the most important thing to do is take a moment to ponder, “What can I say that is authentic and professional?”In the end, honesty is best. This might include saying that you don’t have an exact answer or even admitting that it’s a challenging question. What doesn’t work is posturing, sugarcoating or pretending you know something you don’t. Gaining the interviewer’s respect will always be more important than having a “perfect” answer.