Jenny was a little nervous in front of so many strangers at  first. But when she glanced at Jack,

she immediately   felt _____ .   [ ]

A. in peace  

B. in need      

C. at a loss    

D. at ease

施工现场各类洞口等危险处，除设置防护设施与安全标志外，夜间还应设（）示警。

A、彩灯

B、白炽灯

C、彩灯

D、红灯