执行以下程序后，test.txt文件的内容是(若文件能正常打开) ( )。#include ＜stdio.h＞#include ＜stdlib.h＞main( ) FILE * fp; char * s1 = "Fortran" , * s2 = "Basic"; if((fp = fopen( "test. txt" ," wb" )) = = NULL) prinff( "Can’t open test. txt file \n"); exit(1); fwrite( s1 ,7,1 ,fp); /* 把从地址s1开始到7个字符写到fp所指文件中*/ fseek(fp,OL,SEEK_SET); /*文件位置指针移到文件开头*/ fwrite (s2,5,1,fp); felose (fp); A: Basiean B: BasieFortran C: Basic D: FortranBasie