有定义语句：int i; char s1[10], s2[10]= "Program"; 则能正确给s1数组赋字符串的语句是

• A.for(i=0; i<=7; i++) s1[i]=s2[i];

• B.s1=s2;

• C.while(s2) s1++ =s2++;

• D.for(i=0; s2[i]; i++ ) s1[i]=s2[i];