—_______ I borrow your calculator?

—of course you can.[ ]

A. Must

B. Can

C. Should

D. Will

有如下程序
main()
int x=1,a=0,b=0;
switch(x)
case 0: b++;
case 1: a++;
case 2: a++;b++;

printf("a=%d,b=%d\n",a,b);

该程序的输出结果是______。

A．a=2,b=1

B．a=1,b=1

C．a=1,b=0

D．a=2,b=2