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;y=t;} } main( ) { int a=4,b=3,c=5; f(a,b); f(a,c); f(b,c); cout<<a<<","<<b<<","<<c<<endl; } 执行后输出结果是

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