单项选择题

有以下程序 #include <stdio.h> main() { FILE *fp;int i,k=0,n=0; fp=fopen("d1.dat","w"); for(i=1;i<4;i++)fprintf(fp,"%d",i); fclose(fp); fp=fopen("d1.dat","r"); fscanf(fp,"%d%d",&k,&n);printf("%d%d\n",k,n); fclose(fp); } 执行后输出结果是

A.1 2
B.123 0
C.1 23
D.0 0