有以下程序

#include<stdio.h>

main()

{FILE *fp; int i,a[6]={l,2,3,4,5,6};

fp=fopen("d3.dat","w+b");

fwrite(a,sizeof(int),6,fp);

fseek(fp,sizeof(int)*3,SEEK_SET);/*该语句使读文件的位置指针从文件头向后移动3个int型数据*/

fread(a,sizeof(int),3,fp); fclose(fp);

for(i=0;i<6;i++)printf("%d,",a[i]);

}

程序运行后的输出结果是

A．4,5,6,4,5,6,

B．1,2,3,4,5,6,

C．4,5,6,1,2,3,

D．6,5,4,3,2,1,