s1和s2已正确定义并分别表示两个字符串，若要求当s1所指字符串大于s2所指字符串时，输出ok，则以下选项中正确的是（）。

A.if（strcmp（s2,s1）= =0）ST;

B.if（sl= =s2）ST;

C.if（strcpy（s l ,s2）= =1）ST;

D.if（sl-s2 = =0 ）ST;

A.if(s1==s2)

B.if(s1=s2)

C.if(strcpy(s1,s2))

D.if(strcmp(s1,s2)==0)

A.if(sl>s2)

B.if(strcmp(sl,s2)>0)

C.if(strcmp(s2,s1)>0)

D.if(strcmp(sl,s2))

A.if (S1=S2)

B.if (S1==S2)

C.if (strcpy(S1,S2))

D.if (strcmp(S1,S2)==0)

A.if(S1=S2)

B.if(S1==S2)

C.if(strcpy(S1,S2))

D.if(strcmp(S1,S2)==0)

A.if(strcmp(s1,s2)==0) puts(s1);

B.if(strcmp(s1,s2)!=0) puts(s2);

C.if(strcmp(s1,s2)==1) puts(s1);

D.if(strcmp(s1,s2)!=0) puts(s1);

A.if(!strcmp(s1,s2)) puts(“Equal.”);

B.if(s1==s2) puts(“Equal.”)

C.if(*s1==*s2) puts(“Equal.”)

D.if(strcmp(s1,s2)) puts(“Equal.”);