cos

It's not written for a Japanese audience, so the meaning of the word inside Japan only isn't what I had in mind, but I don't think it actually matters. If you're referring to the question I think you are, there's one answer that's clearly best (and scores the most points), and one other answer that's clearly not best but still scores a bit because it shows the person has some familiarity with the term. Some answers are very obviously wrong and you'll lose a point for those. The correct answers are also the ones someone in Japan would choose.

P.S. I slightly adjusted the wording of a couple of answers on that question due to your comment.