单选题：下列程序的输出结果是

下列程序的输出结果是 @[C](3)
```
int fun(int x) {
static int a = 3;
a += x;
return (a);
}

int main()
{
int k = 2, m = 1, n;
n = fun(k); n = fun(m);
printf("%d\n", n);
return 0;
}
```
A. 5
B. 4
C. 6
D. 3




A.5
B.4
C.6
D.3


答案：C