- Could you give me a hand?

- Well, please tell me_______ it is first.

A．which

B．how

C．where

D．what

下列程序的输出结果是______。
main()
int a=1,b=2,c=3,t=0;
if(a＜B) t=a;a=b;b=t;
if(a＜C) t=a;a=c;c=t;
printf("%d,%d,%d\n",a,b,c);