in the qucue for half an hour the old man auddenly realized he had left the cheque in the

问题补充：

in the qucue for half an hour ,the old man auddenly realized he had left the cheque in the car.

A. Waiting

B. To wait

C. Having waited

D. To have waited

答案：

A. Waiting

B. To wait

(答案→)C. Having waited

D. To have waited

解析：有明显的先后关系，故要用V-ing的完成式。