in the war many children have become orphans(孤儿).A. Their parents were killedB. Being ki

问题补充：

in the war, many children have become orphans(孤儿).

A. Their parents were killed

B. Being killed

C. Their parents killed

D. Killed

答案：

A. Their parents were killed

B. Being killed

(答案→)C. Their parents killed

D. Killed

解析：考查独立主格结构。根据句中逗号可知考查非谓语动词，their parent与kill为被动关系，故用过去分词，选C。