有以下程序
#include
void  main( )
{ 
    int a ;
    scanf("%d",&a);
    if(a >= 0)
    {
        if( a % 2 ==0)
            printf("%d is a positive even number.\n", a);
        else
            printf("%d is a positive odd number.\n", a);
    }
    else
    {
        if( a % 2 ==0)
            printf("%d is a negative even number.\n", a);
        else
            printf("%d is a negative odd number.\n", a);
    }
}
若通过键盘输入-11，则运行结果是(    )。
A、-11 is a negative odd number.
B、11 is a negative even number.
C、-11 is a positive odd number.
D、-11 is a positive even number.