— Excuse me, would you please give_________ magazine to Mary?

— Sorry, but I don’t think there is_________ Mary in my class.

A．a; /

B．the; /

C．the; a

D．a; a

下面程序的运行结果为【 】。　　# include ＜iostream．h＞　　void fun(int x=0，int y=0)　　{　　　　cout ＜＜ X ＜＜ y；　　＝　　void main(　)　　{　　　　fun(5)；　　}