单选题：如下程序的执行结果是

如下程序的执行结果是 @[C](2)
```c++
#include
int main (void)
{
int i, sum = 0;
for ( i = 1; i <= 3; sum ++ )
sum += i ;
printf ("%d\n", sum);
return 0;
}
```
A. 6
B. 3
C. 死循环
D. 0





A.6
B.3
C.死循环
D.0


答案：C