以下属于实时清算系统的是（）
A、批量清算子系统
B、清算中心子系统
C、批量对帐子系统
D、以上都是
参考答案：D
His mother was in hospital. He asked for ___ to look after his mother.
A．three-day’s sick leave
B．three day’s sick leave
C．three days’ sick leave
D．three-days’ sick leave
法律和党的政策最主要的区别在于前者具有规范性，后者不具有规范性。 ( )
