—Was the driving pleasant when you went to Mexico last summer?

—No, it ________ (rain) for four days when we arrived, so the roads were very muddy.

房屋建筑安装工程施工安全措施的主要关注点（）。

A.高空作业

B.施工机械操作

C.生活区的选址应符合安全性要求

D.起重吊装作业

E.在密闭容器内作业