Please choose another topic ___you still have something else to say about this.

题目

Please choose another topic ___you still have something else to say about this.
选项：A.though B.unless C.if D.because
我选的是B,但正确答案是A,

答案

选B 这个句子的意思是“除非你还有什么要说的,否则就再换个话题吧” unless=“除非”