— Hello, _____ is Cindy speaking.
— Hello, _________ Tom here.
A:I'm; it's
B:this; it's
C:it; I'm
D:that's; it's
将一根枝条插入滴有红墨水的瓶中,放在太阳下一段时间后,将枝条从切开来,用放大镜可看出哪一部分被染红了( )