单选题：请问程序段的输出结果是（）。

请问程序段的输出结果是（）。
```
	FILE *fp;
	int x=12,y=34;
	fp=fopen("test.txt","w");
	fprintf(fp,"%d%d",x,y);
	fclose(fp);
	fp=fopen("test.txt","r");
	fscanf(fp,"%d",&x);
	printf("%d,%d",x,y);
	fclose(fp);
```



A.1234,34
B.12,34
C.1234
D.123434


答案：A