There is only one answer to that.
那只有一个答案。
答案只有一个。
The question permits of only one answer.
那个问题只许有一个答案。
Click on only one answer for each question.
每个问题只按选一个答案。
To those who asked it, only one answer was acceptable.
对于问起这事的人，只有一种回答是可以接受的。
Only one answer I can think of.
我能想到的唯一答案。
Only one answer, raw material rare!
答案只有一个，原料稀少！
Only one answer, raw material rare!
答案只有一个，原料稀少！
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