问题
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;
B:when would the policeman come
C:what her students have done during the trip
D:if her students had survived the earthquake;
正确答案是：
