室间隔缺损患者有时出现声音嘶哑，其原因最可能是()

A．扩张的右心房压迫喉返神经

B．扩张的左心房压迫喉返神经

C．扩张的主动脉压迫喉返神经

D．扩张的肺动脉压迫喉返神经

E．扩张的左、右心房压迫喉返神经

You_____ all those calculations! We have a computer to do that sort of thing.

A．needn’t have done

B．must not have done

C．shouldn’t have done

D．can not have done