“夷洲”、“流求”、“琉球”是我国某地区不同时期的名称。请问我国从何时开始正式管辖该地区( )
A:三国
B:隋朝
C:元朝
D:清朝
He has bought a new camera. He is _______.
—It _______ be him. I saw him enter the school library just now.