日前，广东省珠海市      -规划蓝图确定：在“一国两制”下探索粤港澳紧密合作的示范区、深化改革开放和科技创新的先行区、促进珠江口西岸地区产业升级的新平台。

A珠海新区       B大亚湾新区         C九龙新区     D横琴新区

Somebody rang my doorbell just now, but I didn't know _____. [ ]

A. who were they

B. who they were

C. who it was