The bell the end of the period rang our heated discussion.A. indicating; interruptingB.

问题补充：

The bell the end of the period rang, our heated discussion.

A. indicating; interrupting

B. indicated; interrupting

C. indicating; interrupted

D. indicated; interrupted

答案：

(答案→)A. indicating; interrupting

B. indicated; interrupting

C. indicating; interrupted

D. indicated; interrupted

解析：句意：表明这一段时间结束的铃声响起来了，打断了我们热烈的讨论。本句谓语动词为rang，其余出现的动词都为非谓语动词，indicate,interrupt的逻辑主语均为the bell,主动关系，故选A.