【题目】Living in the central Australian desert has its problems, _____ obtaining water is not the least.
A. of which B. for what
C. as D. whose
在线课程【答案】A
【解析】本题中含有一个定语从句，先行词是its problems，定语从句中的关系代词which指代前面的先行词problems在句中作为of的宾语。介词of表示所属关系。句意：生活在澳大利亚中部有很多问题，找到水是并不是最糟糕的那一个。What不能引导定语下句，as和whose和本句的结构不相符。故A正确。