.alone in a dark room the little girl was so at the sound. A. Left; frightening; fright

问题补充：

.alone in a dark room, the little girl was so at the sound.

A. Left; frightening; frightening

B. Left; frightened; frightening

C. Leaving; frightened; frightening

D. Leaving; frightening; frightened

答案：

A. Left; frightening; frightening

(答案→)B. Left; frightened; frightening

C. Leaving; frightened; frightening

D. Leaving; frightening; frightened

解析：考查非谓语动词。the little girl与leave之间是被动关系，，所以用过去分词作状语，frightened 感到害怕的，修饰人，frightening 令人害怕的，修饰物，句意：这个小男孩被单独留在一间漆黑的房间，她听到这个害怕的声音感到如此的害怕。所以选B。