以下程序的输出结果是______。
int fun(int*x, int n)
if(n==0) return x[0];
else return x[0]+fun(x+l, n-1);

main()
int a[]=1, 2, 3, 4, 5, 6, 7; printf("%d\n", fun(a, 3));

—We’ve missed the last bus! Now We’ll have to walk home．

Yes, we       the library five minutes earlier．

A．would have left

B．must have left

C．might have left

D．should have left