There were lots of people and not one of them offered to help. A. standing watchingB. s

问题补充：

There were lots of people ， and not one of them offered to help.

A. standing watching

B. standing to watch

C. stood watching

D. stood to watch

答案：

(答案→)A. standing watching

B. standing to watch

C. stood watching

D. stood to watch

解析：现在分词短语 standing watching 在此用作后置定语，句意为：当时有许多人站着观看，但其中没有一个人主动提供帮助。