第15题:[单选题]Much of the debate on an ongoing society in China has focused on the extended families __________ the number of “empty-nets”is growing by the millions every year. A.that B.when C.where D.which 参考答案:C 考查定语从句。该句中先行词families在从句中作状语，所以应该用关系副词，that和which是关系代词，可以排除。先行词families不表示时间，排除B。关系副词在定语从句中相当于“介词+which”。这里where=in which，表示地点。
