—Why did Miss Yang look so worried when we saw her?

—Because she wondered __________.

A．where did the other students go

B．when would the policeman come

C．what her students have done during the trip

D．if her students had survived the earthquake

在建设项目决策的原则中，民主决策原则主要包括______。

A．数据资料可靠

B．独立咨询机构参与

C．专家论证

D．公众参与

E．科学方法