In the last few years thousands of films______ all over the world.[ ]

A. have produced  

B. have been produced

C. are producing  

D. are being produced

装备矿井安全监控系统的矿井，主要通风机、局部通风机应设置（）。

A、风速传感器

B、开关传感器

C、一氧化碳传感器

D、设备开停传感器