As it turned out to be a small house party, we _______ so formally.

A．needn’t dress up

B．didn’t have to dress up

C．might not have dressed up

D．needn’t have dressed up

若有以下程序：
#include ＜iostream＞
using namespace std;
int main()

int a[4] [4] = 1,2,3,-4,0,-12,-13,14,
-21,23,0,-24,-31,32,-33,0;
int i,j,s = 0;
for(i=0;i＜4;i++)

for(j=O;j＜4;j++)

if(a[i] [j] ＞=0)
continue;
s+=a [i] [j];


cout＜＜s＜＜end1;
return 0;

执行后的输出结果是( )。

A．-138

B．141

C．75

D．-1