The road was so narrow that there would be traffic jams____, especially during the rush hour.

A．every now and then

B．more or less

C．from then on

D．up and down

配置访问控制列表必须作的配置是（）

A、设定时间段

B、制定日志主机

C、定义访问控制列表

D、在接口上应用访问控制列表