You can't go to Australia this afternoon ( ) you don't mind a

You can't go to Australia this afternoon ( ) you don't mind a stopover in Singapore.
A、if
B、unless
C、because
D、until
【正确答案】：B
【题目解析】：考核关联词含义，句子含义是除非你不介意在新加坡做中转，否则今天下午你去不了澳大利亚。