单选题The family is a coop

问题补充：

单选题Thefamilyisacooperativeenterpriseforwhichitisdifficultto_____rules,becauseeachfamilyneedstoworkoutitsownwaystodealwithitsownproblems.A.set upB.put downC.keep upD.lay down

答案：

D解析lay down制定符合句意；A建立，创立；C保持。