The winner of the Grand Slams said that he had owed his success to many people, his parents_________.

A．after all

B．by chance

C．on purpose

D．in particular

在操作系统中的所谓虚拟是指通过某种技术把一个( )变成若干个逻辑上的对应物。

A．物理实体

B．逻辑实体

C．虚拟实体

D．虚处理机