脑梗塞患者CT图象为（）。

A.起病后即可见异常低密度影

B.起病24～48h后可见异常低密度影

C.起病后即可见异常高密度影

D.起病24～48h后可见异常高密度影

E.起病一周后才改变

A digital ring is locked on every newborn baby’s foot _______ they are taken by strangers out of the hospital.

A．because

B．when

C．so that

D．in case