—Excuse me Mum. When can we have dinner? —Not until it in half an hour.A. is prepared B.

问题补充：

—Excuse me, Mum. When can we have dinner?

—Not until it in half an hour.

A. is prepared

B. will be prepared

C. had been prepared

D. was prepared

答案：

(答案→)A. is prepared

B. will be prepared

C. had been prepared

D. was prepared

解析：句意：打扰了，妈妈。我们什么时候可以吃饭？——再有半个小时就准备好了。结合语境可知下文为省略句，根据连词until可知后面状语从句，根据语境及时间状语可知下文主句描述的是将来的动作，故条件从句中用一般现在时态表示将来动作，故选A。