【单选题】运行下面程序时,若从键盘输入数据为"123",则输出结果是________.#include "stdio.h"void main(){ int num,i,j,k,place;scanf("%d",&num);if (num>99)place=3;else if(num>9)place=2;elseplace=1;i=num/100;j=(num-i*100)/10;k=(num-i*100-j*10);switch (place){ case 3: printf("%d%d%d\n",k,j,i);break;case 2: printf("%d%d\n",k,j);break;case 1: printf("%d\n",k);}}

A. 123
B. 1,2,3
C. 321
D. 3,2,1