执行以下程序后，tEst.txt文件的内容是(若文件能正常打开)______。#inCluDE mAin(){ FilE、*Fp;ChAr *s1="FortrAn",*s2="BAsiC";iF((Fp=FopEn("tEst.txt","wB"))==null){ printF("CAn’’t opEn tEst.txt FilE\n"); Exit(1);}FwritE(s1,7,1,Fp); /*把从地址s1开始的7个字符写到Fp所指文件中*/F sEEk(Fp, 0l,sEEk_sEt); /*文件位置指针移到文件开头*/FwritE(s2,5,1,Fp);FClosE(Fp);}A．BAsiCAn
BAsiCFortrAn
C、BAsiC
D．FortrAnBAsiC