________ entering the tall building, he heard a sharp cry coming out of it, which brought his heart to his mouth.
A.Upon B.At
C.In D.With
________ entering the tall building, he heard a sharp cry coming out of it, which brought his heart to his mouth.
A.Upon B.At
C.In D.With
解析:句意:他一走进这座高楼,就听到里面发出尖叫声,吓得他心都跳到嗓子眼了。“upon/on+动名词/名词”意为“一……就……”。
答案:A