These natural disasters have warned us that everyone should start to protect the _____ immediately. [ ]

A. amusement

B. development

C. environment

D. government

因违反有关规定而被强迫降落的外国民用航空器，只有得到（）的许可，才能继续飞行。

A.民航总局

B.外交部

C.当地空军

D.民航地区管理局