单项选择题

有以下程序:  
#include<stdi0.h>  
main() {
FILE *fp;
int i=20,j=50,k,n; 
  fp=fopen("d1.dat","W");
  fprintf(fp,"%d\n",i);
fprintf(fp,"%d\n",j); 
  fclose(fp); 
  fp=fopen("d1.dat","r",);  
  fscanf(fp,"%d%d",&k,&n);
printf("%d%d\n",k,n); 
  fclose(fp);  
}  
 程序运行后的输出结果是()

A.20 30
B.20 50
C.30 50
D.30 20