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

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：考查非谓语动词。do nothing but (to) do除了……. 别无选择，根据含义选择D。