He chose to teach in a mountain village, though he       in the city for a better life.

A．could stay

B．would stay

C．could have stayed

D．should have stayed

综合安全技术

起爆药、击发药、火工品制造的场所，电气设备表面温度不得超过允许表面温度，且符合防爆电气设备的有关规定，优先采用( )。

A．Ⅰ类B级隔爆型

B．密封型

C．防水防尘型

D．防粉尘点火型