外用杀虫止痒，内服壮阳通便的药物是( )
A．雄黄
B．硫黄
C．蛇床子
D．巴戟天
E．杜仲
参考答案：B
Choose the right answer for the last picture.
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A. It's a watch!
B. The watch is new.
C. It must be a watch.
D. Oh! My watch!
计算机机联锁系统应具有对室外联锁设备的（）功能。
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