单项选择题

有以下程序void f(int x,int y){ int t, if(x<y){t=x;x=y;t;}}main(){ int a=4,b=3,c=5; f(a,B) ;f(a,C) ;f(b,C) ; cout<<a<<","<<b<<","<<c<<end1;}执行后输出结果是

A.3,4,5
B.5,3,4
C.5,4,3
D.4,3,5