His mother could do nothing but for the doctor to arrive. A. to waitB. waitingC. waited

问题补充：

His mother could do nothing but for the doctor to arrive.

A. to wait

B. waiting

C. waited

D. wait

答案：

A. to wait

B. waiting

C. waited

(答案→)D. wait

解析：考查固定用法。can/could do nothing but do sth else别无选择只好做某事。“前有do后省to”，当前面出现do时，后面省略不定式符号to。故选D。