有以下程序 include main(){FILE *fp;int i; char ch[]="abcd",t; fp=fopen("abc.dat"

有以下程序 #include ＜stdio.h＞ main() {FILE *fp; int i; char ch[]="abcd",t; fp=fopen("abc.dat","wb＋＋"); for(i=O;i＜4;i＋＋)fwrite(&ch[i],1,1,fp); fseek (fp,-2L,SEEK_END); fread (&t,1,1,fp); fclose (fp); printf ("%c/n",t); } 程序执行后的输出结果是______。

A．d

B．c

C．b

D．a