—I haven’t worked the problem out yet. What am I supposed to do?      

—Try again! It’s only _________ difficult.[ ]

A. a lot    

B. a bit          

C. too much    

D. too many

下列程序的输出结果是( )。
#include ＜stdio.h＞
#define M(x, y) x%y
main()
int a, m=12, n=100;
a=M(n, m);
printf("%d\n", a--);

A) 2
B) 3
C) 4
D) 5