Hi Jessica, what is the best thing you can say if you don't know an answer to a question?
Depends on the nature of the question and how badly you don't know the answer. It could be any of the following (and a whole lot more)….:
"I don't know the answer to this, but I would have thought....."
"Please could you explain that a little more..."
"I am unsure, but I think the answer is"
"I don't know much about that subject, whether now or at the end of the interview, I'd be interesting in learning from you to understand what it means though"
"Please can I have some time to think about that and come back to that question later"
"Would you mind if I just take a moment to think about my answer"
"I haven't had the opportunity to gain knowledge about that yet, but it is something I am hoping to learn about in the near future".
Basically the only bad answer is "I don't know" because you cut off your answer there and your interviewer hasn't really got anywhere to go with it. As long as you show a willingness to either give the answer a go (but acknowledge it might not be right) or show a willingness to learn what the answer might be, any other response is ok.