We have been excavating layers of ash almost six metres thick, which suggests that they________the fire burning all winter.

A．should keep

B．might have kept

C．should have kept

D．might keep

区别政府有无权威的根本标志是

A政府的“红头文件”是否下发到群众手里

B政府的管理是否被人民自觉地认可和服从

C政府能否不断提升居民的工资水平      

D政府能否为百姓包办一切